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diff --git a/2025/captions/emacsconf-2025-calc--basic-calc-functionality-for-engineering-or-electronics--christopher-howard--main--chapters.vtt b/2025/captions/emacsconf-2025-calc--basic-calc-functionality-for-engineering-or-electronics--christopher-howard--main--chapters.vtt new file mode 100644 index 00000000..f3af8a6f --- /dev/null +++ b/2025/captions/emacsconf-2025-calc--basic-calc-functionality-for-engineering-or-electronics--christopher-howard--main--chapters.vtt @@ -0,0 +1,41 @@ +WEBVTT + + +00:00:03.620 --> 00:02:36.639 +Introduction + +00:02:36.640 --> 00:04:54.279 +What is Calc? + +00:04:54.280 --> 00:06:37.398 +calc-algebraic-entry + +00:06:37.399 --> 00:08:07.759 +calc-roll-down + +00:08:07.760 --> 00:08:58.179 +Advanced functions + +00:08:58.180 --> 00:09:54.719 +Solving equations with calc-solve-for + +00:09:54.720 --> 00:12:00.079 +Systems of equations + +00:12:00.080 --> 00:12:39.959 +calc-find-root + +00:12:39.960 --> 00:14:17.539 +Derivatives and integrals + +00:14:17.540 --> 00:18:12.159 +Programmable functions + +00:18:12.160 --> 00:20:08.799 +Plotting + +00:20:08.800 --> 00:22:38.599 +Wish list + +00:22:38.600 --> 00:23:35.920 +Wrapping up diff --git a/2025/captions/emacsconf-2025-calc--basic-calc-functionality-for-engineering-or-electronics--christopher-howard--main.vtt b/2025/captions/emacsconf-2025-calc--basic-calc-functionality-for-engineering-or-electronics--christopher-howard--main.vtt new file mode 100644 index 00000000..f0bf2d2a --- /dev/null +++ b/2025/captions/emacsconf-2025-calc--basic-calc-functionality-for-engineering-or-electronics--christopher-howard--main.vtt @@ -0,0 +1,888 @@ +WEBVTT captioned by sachac + +NOTE Introduction + +00:00:03.620 --> 00:00:08.799 +Hello, my name is Christopher Howard and welcome to my talk. + +00:00:08.800 --> 00:00:11.319 +This is basically an introduction + +00:00:11.320 --> 00:00:15.119 +to the built-in Emacs calculator, + +00:00:15.120 --> 00:00:18.319 +properly known as Emacs Calc, + +00:00:18.320 --> 00:00:21.439 +particularly from the perspective of someone + +00:00:21.440 --> 00:00:27.559 +with a technical background such as engineering or electronics. + +00:00:27.560 --> 00:00:32.879 +I will say, though, my personal interest is not really + +00:00:32.880 --> 00:00:37.839 +in digital computing or digital calculators, + +00:00:37.840 --> 00:00:42.519 +but lately has been focused more on analog computing. + +00:00:42.520 --> 00:00:46.799 +I have, for example, been working to master + +00:00:46.800 --> 00:00:50.839 +the venerable slide rule, a mechanical computer + +00:00:50.840 --> 00:00:57.319 +that calculates multiplication powers and logarithms. + +00:00:57.320 --> 00:01:02.199 +Here's a picture of one. + +00:01:02.200 --> 00:01:06.799 +It's a physical tool that was used for hundreds of years + +00:01:06.800 --> 00:01:08.999 +for this sort of thing + +00:01:09.000 --> 00:01:16.679 +before the handheld calculator was made popular. + +00:01:16.680 --> 00:01:18.639 +And I also had a project that I did + +00:01:18.640 --> 00:01:21.119 +for a while to several months + +00:01:21.120 --> 00:01:33.119 +to build an electronic analog computer. + +00:01:33.120 --> 00:01:38.679 +A rudimentary attempt of mine, but it's functional, + +00:01:38.680 --> 00:01:43.399 +and it's basically a 1960s or 1970s style + +00:01:43.400 --> 00:01:48.839 +electronic analog computer built very much on a budget, + +00:01:48.840 --> 00:01:52.559 +but the box in the middle is the computer proper + +00:01:52.560 --> 00:01:55.719 +which has most of the components inside of it + +00:01:55.720 --> 00:02:00.199 +as well as the potentiometers for setting values, + +00:02:00.200 --> 00:02:02.039 +and an operation switch. + +00:02:02.040 --> 00:02:04.399 +There's a patch panel on the left + +00:02:04.400 --> 00:02:07.119 +for connecting the different integrators, + +00:02:07.120 --> 00:02:11.319 +amplifiers, multipliers, and so forth together. + +00:02:11.320 --> 00:02:16.919 +Then the output of the simulation is displayed + +00:02:16.920 --> 00:02:19.799 +on the oscilloscope on the right side, + +00:02:19.800 --> 00:02:25.479 +which is a digital oscilloscope. + +00:02:25.480 --> 00:02:28.439 +To be honest, I think that a talk about analog computing + +00:02:28.440 --> 00:02:30.199 +would be much more interesting + +00:02:30.200 --> 00:02:32.039 +than the talk that I'm about to give, + +00:02:32.040 --> 00:02:36.639 +but unfortunately that would be out of scope for EmacsConf. + +NOTE What is Calc? + +00:02:36.640 --> 00:02:39.919 +So instead I will talk about Emacs Calc, + +00:02:39.920 --> 00:02:43.359 +the digital calculator built into Emacs. + +00:02:43.360 --> 00:02:47.519 +Emacs Calc, while not being a replacement for software + +00:02:47.520 --> 00:02:51.479 +like GNU Octave, does have advanced calculator functionality + +00:02:51.480 --> 00:02:55.039 +that can be useful in engineering, electronics, + +00:02:55.040 --> 00:03:00.759 +or other technical applications. So I don't want to oversell it, + +00:03:00.760 --> 00:03:06.479 +but I think functionality-wise, Calc is somewhere in between + +00:03:06.480 --> 00:03:12.239 +what you'd expect of a decent scientific calculator + +00:03:12.240 --> 00:03:23.939 +and an advanced graphics calculator. + +00:03:23.940 --> 00:03:28.839 +So this talk I'll mention is not intended to be a tutorial + +00:03:28.840 --> 00:03:33.839 +but only a brief introduction to Calc. + +00:03:33.840 --> 00:03:37.439 +Please refer to the built-in Calc info manual + +00:03:37.440 --> 00:03:46.739 +for detailed instructions on how to complete operations. + +00:03:46.740 --> 00:04:01.479 +Turn off my volume here. + +00:04:01.480 --> 00:04:05.719 +The documentation for Emacs Calc is built-in, + +00:04:05.720 --> 00:04:10.439 +although on some distributions you may have to install + +00:04:10.440 --> 00:04:24.479 +the Emacs documentation separately for licensing reasons. + +00:04:24.480 --> 00:04:28.599 +Calc presents itself as a stack-based calculator + +00:04:28.600 --> 00:04:31.599 +where entries are dropped onto a stack + +00:04:31.600 --> 00:04:36.739 +and then an operation is performed on the stack entries. + +00:04:36.740 --> 00:04:42.899 +For example, I can drop 1.23 onto the stack, + +00:04:42.900 --> 00:04:54.279 +and then 8.56, and then multiply them together. + +NOTE calc-algebraic-entry + +00:04:54.280 --> 00:05:01.559 +It may present itself as a stack-based calculator, + +00:05:01.560 --> 00:05:05.399 +but indeed, Calc is also capable of accepting input + +00:05:05.400 --> 00:05:07.739 +in the more well-known algebraic format + +00:05:07.740 --> 00:05:10.759 +by using the calc-algebraic-entry command, + +00:05:10.760 --> 00:05:14.999 +which by default is bound to the apostrophe (') key. + +00:05:15.000 --> 00:05:19.759 +So you type the apostrophe key, enter the algebraic input, + +00:05:19.760 --> 00:05:22.759 +including parentheses as needed. + +00:05:22.760 --> 00:05:28.199 +For example, here's a calculation of the resonance frequency + +00:05:28.200 --> 00:05:35.039 +of a coil which has an inductance of 250 microhenries + +00:05:35.040 --> 00:05:41.059 +and 160 picofarads, taken from one of my electronics handbooks. + +00:05:41.060 --> 00:05:50.019 +The formula for that is 1 over 2 pi + +00:05:50.020 --> 00:05:57.439 +and then the square root of our inductance + +00:05:57.440 --> 00:06:06.279 +which is in this case 250 microfarads - excuse me, microhenries + +00:06:06.280 --> 00:06:19.399 +and then the capacitance is 160 picofarads. + +00:06:19.400 --> 00:06:24.399 +Small typo here. + +00:06:24.400 --> 00:06:26.639 +Now I need to evaluate that one more time, + +00:06:26.640 --> 00:06:30.919 +because pi is a symbol. + +00:06:30.920 --> 00:06:37.398 +I get about 800 kHz resonant frequency. + +NOTE calc-roll-down + +00:06:37.399 --> 00:06:41.679 +The command calc-roll-down, + +00:06:41.680 --> 00:06:44.199 +which by default is bound to the TAB key, + +00:06:44.200 --> 00:06:47.919 +will swap the top two stack entries, + +00:06:47.920 --> 00:06:51.559 +which is sometimes useful if you need to manipulate something + +00:06:51.560 --> 00:06:56.999 +that's further down the stack. + +00:06:57.000 --> 00:07:02.039 +So I can swap this around and say multiply by two + +00:07:02.040 --> 00:07:05.479 +and then put it back where it was. + +00:07:05.480 --> 00:07:14.039 +This command is also capable of rolling the entire stack. + +00:07:14.040 --> 00:07:18.899 +Say I want to shift them all around. + +00:07:18.900 --> 00:07:21.399 +This can be done by passing extra arguments + +00:07:21.400 --> 00:07:23.559 +to the calc-roll-down function. + +00:07:23.560 --> 00:07:28.279 +That's a little bit inconvenient to do manually, + +00:07:28.280 --> 00:07:40.079 +so in my init file, I defined here a key definition + +00:07:40.080 --> 00:07:45.759 +that passes in those arguments correctly. + +00:07:45.760 --> 00:07:49.179 +I attached this to shift-tab, + +00:07:49.180 --> 00:07:52.319 +so this way, I can roll the entire stack. + +00:07:52.320 --> 00:07:56.159 +Then I could change one entry here + +00:07:56.160 --> 00:08:03.459 +and then put it back where it was. + +00:08:03.460 --> 00:08:07.759 +So Calc does algebraic input. + +NOTE Advanced functions + +00:08:07.760 --> 00:08:10.159 +It also does advanced functions + +00:08:10.160 --> 00:08:15.599 +that you would expect any handheld scientific calculator, + +00:08:15.600 --> 00:08:19.159 +including trigonometric functions. + +00:08:19.160 --> 00:08:25.319 +For example, we can get the sine of a number. + +00:08:25.320 --> 00:08:30.719 +Now I'll mention here that Calc has multiple modes. + +00:08:30.720 --> 00:08:32.319 +Right now it's in degree mode. + +00:08:32.320 --> 00:08:38.159 +You can switch over to radian mode if you want. + +00:08:38.160 --> 00:08:42.799 +I'm going to put it back in degrees. + +00:08:42.800 --> 00:08:49.799 +Drop 12 degrees on the stack, and then get the sine of that. + +00:08:49.800 --> 00:08:58.179 +And then with the inverse sine function, I can put it back. + +NOTE Solving equations with calc-solve-for + +00:08:58.180 --> 00:09:07.519 +Calc also has the nifty ability to solve equations for you + +00:09:07.520 --> 00:09:13.919 +so long as the equation is not too complicated. + +00:09:13.920 --> 00:09:19.959 +This is using the calc-solve-for function. + +00:09:19.960 --> 00:09:31.699 +For example, we could enter in an equation algebraically, + +00:09:31.700 --> 00:09:36.679 +then run calc-solve-for, and we just have to tell it + +00:09:36.680 --> 00:09:40.999 +what variable we want to solve for. And there we go. + +00:09:41.000 --> 00:09:43.199 +We can do this manually as well + +00:09:43.200 --> 00:09:54.719 +just so you can see that we get the same result. + +NOTE Systems of equations + +00:09:54.720 --> 00:09:57.959 +Calc is also able to solve systems of equations. + +00:09:57.960 --> 00:10:03.439 +We can put more than one equation on the stack, + +00:10:03.440 --> 00:10:08.959 +and then solve for several variables. + +00:10:08.960 --> 00:10:13.319 +To give a technical example for this, + +00:10:13.320 --> 00:10:30.659 +I'll show you a resistor network scribble that I did recently. + +00:10:30.660 --> 00:10:32.819 +Hopefully you can see that. Basically, + +00:10:32.820 --> 00:10:38.719 +it's fairly simple, a pretty simple resistor network + +00:10:38.720 --> 00:10:42.159 +with 1 kilo ohm and 10 kilo ohm resistors, + +00:10:42.160 --> 00:10:48.959 +and using the loop methods, we are calculating the currents, + +00:10:48.960 --> 00:10:52.759 +the current in each loop, and then that current can be used + +00:10:52.760 --> 00:10:58.839 +to solve for the voltage of each individual resistor + +00:10:58.840 --> 00:11:06.199 +if we want to. So at the bottom there we have the equations + +00:11:06.200 --> 00:11:11.519 +that we come up with as we work through each loop. + +00:11:11.520 --> 00:11:19.579 +And I'm going to paste that into Calc. + +00:11:19.580 --> 00:11:22.719 +To save some time, I'm going to copy and paste that + +00:11:22.720 --> 00:11:34.259 +from my notes instead of typing it out. + +00:11:34.260 --> 00:11:38.259 +So we have two equations there on the stack + +00:11:38.260 --> 00:11:44.719 +in one stack entry. We run that calc-solve-for function again, + +00:11:44.720 --> 00:11:49.899 +and we tell it which variables we want to solve for. + +00:11:49.900 --> 00:11:51.959 +And voila! Those are our currents, + +00:11:51.960 --> 00:11:55.719 +which we can then use to get the voltages + +00:11:55.720 --> 00:12:00.079 +for the individual resistors. + +NOTE calc-find-root + +00:12:00.080 --> 00:12:01.999 +I'll just briefly mention + +00:12:02.000 --> 00:12:05.839 +that if Calc is not able to solve an equation + +00:12:05.840 --> 00:12:07.779 +with calc-solve-for, + +00:12:07.780 --> 00:12:10.279 +then you might be helped by another calc function + +00:12:10.280 --> 00:12:11.559 +called calc-find-root. + +00:12:11.560 --> 00:12:14.439 +This function basically does a manual search + +00:12:14.440 --> 00:12:30.199 +for a numerical solution to the equation. + +00:12:30.200 --> 00:12:39.959 +And there's the documentation page on that. + +NOTE Derivatives and integrals + +00:12:39.960 --> 00:12:44.039 +Calc can also solve or find derivatives of functions, + +00:12:44.040 --> 00:12:47.579 +at least the more straightforward functions. + +00:12:47.580 --> 00:12:49.839 +For a simple example, + +00:12:49.840 --> 00:13:00.559 +we can get the derivative of that + +00:13:00.560 --> 00:13:11.979 +with the derivative function. + +00:13:11.980 --> 00:13:17.159 +On the other hand, Calc is also capable of figuring out + +00:13:17.160 --> 00:13:22.099 +indefinite integrals. + +00:13:22.100 --> 00:13:26.859 +Say we put that function back on the stack, + +00:13:26.860 --> 00:13:32.559 +and this time, we call the integral function. + +00:13:32.560 --> 00:13:35.079 +There you go. Of course, you have to add + +00:13:35.080 --> 00:13:39.819 +your own constant of integration. + +00:13:39.820 --> 00:13:43.399 +For integrals that Calc cannot figure out symbolically, + +00:13:43.400 --> 00:13:46.079 +a numerical integration method is available + +00:13:46.080 --> 00:13:59.998 +through the calc-num-integral command, which is documented... + +00:13:59.999 --> 00:14:17.539 +The function documentation is available here, more or less. + +NOTE Programmable functions + +00:14:17.540 --> 00:14:20.399 +I definitely need to mention + +00:14:20.400 --> 00:14:24.759 +that Calc is capable of doing programmable functions. + +00:14:24.760 --> 00:14:29.619 +That is to say, you can program your own functions into Calc. + +00:14:29.620 --> 00:14:32.239 +There are three separate ways to do this. + +00:14:32.240 --> 00:14:36.279 +One is through a macro method + +00:14:36.280 --> 00:14:41.539 +similar to Emacs's usual keyboard macros. + +00:14:41.540 --> 00:14:46.519 +The second method is to transform an algebraic function + +00:14:46.520 --> 00:14:50.859 +into a stored function definition. + +00:14:50.860 --> 00:14:54.059 +And the third is to use Elisp directly. + +00:14:54.060 --> 00:14:56.599 +Personally, I find that the second method + +00:14:56.600 --> 00:15:01.799 +is the most practical, the most convenient and practical + +00:15:01.800 --> 00:15:08.059 +in my opinion. So I'll give a quick example of that. + +00:15:08.060 --> 00:15:14.159 +So I could... Let's say I wanted to have a function + +00:15:14.160 --> 00:15:20.699 +for calculating capacitive reactance. + +00:15:20.700 --> 00:15:28.899 +I'll define that in algebraic mode first. + +00:15:28.900 --> 00:15:33.639 +The function for that is 1 over 2 pi + +00:15:33.640 --> 00:15:41.599 +the frequency and the capacitance. + +00:15:41.600 --> 00:15:44.959 +Drop that on the stack. You see, it does automatically + +00:15:44.960 --> 00:15:52.079 +get simplified a little bit, but it's the same function. + +00:15:52.080 --> 00:15:58.839 +And then I press letters Z and F. Do that again. + +00:15:58.840 --> 00:16:06.239 +Z and F to start transforming that into a stored function. + +00:16:06.240 --> 00:16:11.039 +It asks me to select a user key, a single key press. + +00:16:11.040 --> 00:16:15.479 +I'll use the letter c. + +00:16:15.480 --> 00:16:19.079 +Then it's going to ask for a longer command name. + +00:16:19.080 --> 00:16:24.639 +I've actually defined this once before, so it prefilled in + +00:16:24.640 --> 00:16:38.339 +that command name. + +00:16:38.340 --> 00:16:42.999 +Then I need to enter which variables in the formula + +00:16:43.000 --> 00:16:46.559 +are actual arguments, rather than just symbols + +00:16:46.560 --> 00:16:52.559 +to be evaluated later. I prefer to put this in with frequency + +00:16:52.560 --> 00:16:54.279 +and the capacitance after that, + +00:16:54.280 --> 00:16:57.799 +but actually in this particular case, + +00:16:57.800 --> 00:17:07.339 +it doesn't matter at all to the mathematics. + +00:17:07.340 --> 00:17:11.399 +So, now all I have to do, that this is defined, + +00:17:11.400 --> 00:17:15.199 +is I can drop the frequency on the stack, + +00:17:15.200 --> 00:17:24.399 +which we'll say, for this example, will be 4.5 MHz, + +00:17:24.400 --> 00:17:32.279 +and then drop on the capacitance, which in this example + +00:17:32.280 --> 00:17:40.319 +will be 22 pF. + +00:17:40.320 --> 00:17:42.439 +Then I'll call the function that I just defined. + +00:17:42.440 --> 00:17:45.239 +I don't really like having to try to remember + +00:17:45.240 --> 00:17:48.679 +the short letters that I've come up with, + +00:17:48.680 --> 00:17:57.839 +so I'll just use the longer name. + +00:17:57.840 --> 00:17:59.799 +I need to evaluate one more time + +00:17:59.800 --> 00:18:05.619 +because the symbol pi is in there and not yet evaluated. + +00:18:05.620 --> 00:18:07.539 +And so if I've done that right, + +00:18:07.540 --> 00:18:12.159 +we have a capacitive reactance of about 1600 ohms. + +NOTE Plotting + +00:18:12.160 --> 00:18:16.839 +As the last feature that I'll mention here, + +00:18:16.840 --> 00:18:24.059 +Emacs Calc does have an interface with gnuplot, + +00:18:24.060 --> 00:18:30.799 +if you want to have Calc work as your graphing calculator. + +00:18:30.800 --> 00:18:33.159 +I do need to be honest and mention + +00:18:33.160 --> 00:18:35.579 +that I don't generally use it myself + +00:18:35.580 --> 00:18:39.719 +because there's another program in GNOME + +00:18:39.720 --> 00:18:43.499 +that I've found to be generally more convenient + +00:18:43.500 --> 00:18:47.399 +for the things that I want to graph quickly. + +00:18:47.400 --> 00:18:53.399 +But I think I can give you a simple example. + +00:18:53.400 --> 00:19:00.339 +So first, we need to drop a range on the stack. + +00:19:00.340 --> 00:19:06.619 +Let's say 0 to 10. + +00:19:06.620 --> 00:19:11.639 +And then we need to drop the function on the stack. + +00:19:11.640 --> 00:19:17.839 +And then I believe it's the letters g and f that graph this. + +00:19:17.840 --> 00:19:22.319 +Let's see. Yep, there we go. + +00:19:22.320 --> 00:19:25.059 +So there's our function and it looks nice. + +00:19:25.060 --> 00:19:26.659 +That was pretty easy. + +00:19:26.660 --> 00:19:29.019 +That's the fast way to do it. + +00:19:29.020 --> 00:19:32.839 +I will, as a disclaimer, mention that + +00:19:32.840 --> 00:19:34.159 +using this quick approach, + +00:19:34.160 --> 00:19:38.759 +that sometimes more complicated graphs + +00:19:38.760 --> 00:19:39.999 +will not turn out nicely, + +00:19:40.000 --> 00:19:44.339 +because by default, the resolution will be pretty low. + +00:19:44.340 --> 00:19:48.119 +That is to say it's... gnuplot is going to be + +00:19:48.120 --> 00:19:49.899 +skipping a lot of points + +00:19:49.900 --> 00:19:52.039 +and so you'll have to learn a bit more + +00:19:52.040 --> 00:19:55.319 +about how to use the interface, + +00:19:55.320 --> 00:19:59.519 +what parameters to pass if you want all your graphs + +00:19:59.520 --> 00:20:03.699 +to come out looking nice. + +00:20:03.700 --> 00:20:08.799 +So that covers all the features that I wanted to cover. + +NOTE Wish list + +00:20:08.800 --> 00:20:13.279 +I wanted to briefly mention a wish list of items + +00:20:13.280 --> 00:20:16.679 +that I'd like to see in Calc. + +00:20:16.680 --> 00:20:23.639 +One of them would be improper integrals. + +00:20:23.640 --> 00:20:25.159 +So that's like our definite integrals + +00:20:25.160 --> 00:20:32.859 +except for where a limit of integration is infinity. + +00:20:32.860 --> 00:20:38.559 +That's something that can be useful in a few applications. + +00:20:38.560 --> 00:20:41.079 +Something else that would be neat to have would be + +00:20:41.080 --> 00:20:45.679 +annotations for row entries. So for example + +00:20:45.680 --> 00:20:48.819 +if I was putting together a sum of numbers + +00:20:48.820 --> 00:20:53.279 +for, say, my monthly budget, + +00:20:53.280 --> 00:20:57.479 +let's say I was paying $2,000 for my rent + +00:20:57.480 --> 00:21:03.831 +and let's say $800 a month for my groceries, + +00:21:03.832 --> 00:21:07.931 +(a lot of kids to feed there) + +00:21:07.932 --> 00:21:14.565 +and then say another $60 for dining out, and so on, + +00:21:14.566 --> 00:21:18.259 +it would be nice if there was some way + +00:21:18.260 --> 00:21:21.319 +to put a little annotation next to each number + +00:21:21.320 --> 00:21:23.399 +so that you could remember + +00:21:23.400 --> 00:21:27.039 +what the meaning of that number was more easily. + +00:21:27.040 --> 00:21:31.199 +I actually looked into programming this into Calc myself, + +00:21:31.200 --> 00:21:35.919 +but discovered that it would require reprogramming + +00:21:35.920 --> 00:21:41.839 +quite a bit of Calc to make that work well + +00:21:41.840 --> 00:21:43.479 +across all calc functionality, + +00:21:43.480 --> 00:21:46.939 +and so, eventually, I gave up. + +00:21:46.940 --> 00:21:51.139 +But I'd still really like to have that feature. + +00:21:51.140 --> 00:21:52.039 +The final thing, though + +00:21:52.040 --> 00:21:54.579 +I think this would not necessarily belong in Calc, + +00:21:54.580 --> 00:21:57.919 +I think it would be cool if Emacs had some way + +00:21:57.920 --> 00:22:00.599 +to run numerical solutions + +00:22:00.600 --> 00:22:02.599 +for systems of differential equations, + +00:22:02.600 --> 00:22:06.019 +also known as a differential analyzer. + +00:22:06.020 --> 00:22:09.279 +So this would allow you to be able to set up simulation models + +00:22:09.280 --> 00:22:11.679 +involving systems of differential equations, + +00:22:11.680 --> 00:22:14.879 +for example, a spring mass system, or pressure temperature, + +00:22:14.880 --> 00:22:18.039 +or what have you, and then run the simulation + +00:22:18.040 --> 00:22:22.119 +using numerical approximation. + +00:22:22.120 --> 00:22:24.079 +Maybe it would be silly + +00:22:24.080 --> 00:22:25.999 +to actually put that in Calc itself, + +00:22:26.000 --> 00:22:30.339 +but a nice interface maybe to some other software, + +00:22:30.340 --> 00:22:33.299 +simple software that did that, + +00:22:33.300 --> 00:22:35.779 +an easy to use interface for that + +00:22:35.780 --> 00:22:38.599 +would be really great. + +NOTE Wrapping up + +00:22:38.600 --> 00:22:41.800 +So that's my entire talk. + +00:22:41.801 --> 00:22:44.534 +I'll just mention some information. + +00:22:44.535 --> 00:22:48.365 +If you want to learn more about me + +00:22:48.366 --> 00:22:50.119 +or things that I'm interested in, + +00:22:50.120 --> 00:22:57.779 +I do not any longer have a web presence. + +00:22:57.780 --> 00:22:59.659 +I don't have a website anymore, + +00:22:59.660 --> 00:23:03.359 +but I do have a Gemini capsule + +00:23:03.360 --> 00:23:07.139 +that I post to all the time. + +00:23:07.140 --> 00:23:13.879 +And if you can install, if you're willing to install the... + +00:23:13.880 --> 00:23:19.079 +Gemini browser known as Elpher + +00:23:19.080 --> 00:23:23.698 +into Emacs, which is available from ELPA, + +00:23:23.699 --> 00:23:27.359 +then you can browse directly to it + +00:23:27.360 --> 00:23:31.439 +and look around my Gemini capsule. + +00:23:31.440 --> 00:23:35.920 +Thank you very much. diff --git a/2025/info/calc-after.md b/2025/info/calc-after.md index 3dbaf680..7c0f6ebf 100644 --- a/2025/info/calc-after.md +++ b/2025/info/calc-after.md @@ -1,6 +1,313 @@ <!-- Automatically generated by emacsconf-publish-after-page --> +<div class="transcript transcript-mainVideo"><a name="calc-mainVideo-transcript"></a><h1>Transcript</h1> + + +<div class="transcript-heading">[[!template new="1" text="""Introduction""" start="00:00:03.620" video="mainVideo-calc" id="subtitle"]]</div>[[!template text="""Hello, my name is Christopher Howard and welcome to my talk.""" start="00:00:03.620" video="mainVideo-calc" id="subtitle"]] +[[!template text="""This is basically an introduction""" start="00:00:08.800" video="mainVideo-calc" id="subtitle"]] +[[!template text="""to the built-in Emacs calculator,""" start="00:00:11.320" video="mainVideo-calc" id="subtitle"]] +[[!template text="""properly known as Emacs Calc,""" start="00:00:15.120" video="mainVideo-calc" id="subtitle"]] +[[!template text="""particularly from the perspective of someone""" start="00:00:18.320" video="mainVideo-calc" id="subtitle"]] +[[!template text="""with a technical background such as engineering or electronics.""" start="00:00:21.440" video="mainVideo-calc" id="subtitle"]] +[[!template text="""I will say, though, my personal interest is not really""" start="00:00:27.560" video="mainVideo-calc" id="subtitle"]] +[[!template text="""in digital computing or digital calculators,""" start="00:00:32.880" video="mainVideo-calc" id="subtitle"]] +[[!template text="""but lately has been focused more on analog computing.""" start="00:00:37.840" video="mainVideo-calc" id="subtitle"]] +[[!template text="""I have, for example, been working to master""" start="00:00:42.520" video="mainVideo-calc" id="subtitle"]] +[[!template text="""the venerable slide rule, a mechanical computer""" start="00:00:46.800" video="mainVideo-calc" id="subtitle"]] +[[!template text="""that calculates multiplication powers and logarithms.""" start="00:00:50.840" video="mainVideo-calc" id="subtitle"]] +[[!template text="""Here's a picture of one.""" start="00:00:57.320" video="mainVideo-calc" id="subtitle"]] +[[!template text="""It's a physical tool that was used for hundreds of years""" start="00:01:02.200" video="mainVideo-calc" id="subtitle"]] +[[!template text="""for this sort of thing""" start="00:01:06.800" video="mainVideo-calc" id="subtitle"]] +[[!template text="""before the handheld calculator was made popular.""" start="00:01:09.000" video="mainVideo-calc" id="subtitle"]] +[[!template text="""And I also had a project that I did""" start="00:01:16.680" video="mainVideo-calc" id="subtitle"]] +[[!template text="""for a while to several months""" start="00:01:18.640" video="mainVideo-calc" id="subtitle"]] +[[!template text="""to build an electronic analog computer.""" start="00:01:21.120" video="mainVideo-calc" id="subtitle"]] +[[!template text="""A rudimentary attempt of mine, but it's functional,""" start="00:01:33.120" video="mainVideo-calc" id="subtitle"]] +[[!template text="""and it's basically a 1960s or 1970s style""" start="00:01:38.680" video="mainVideo-calc" id="subtitle"]] +[[!template text="""electronic analog computer built very much on a budget,""" start="00:01:43.400" video="mainVideo-calc" id="subtitle"]] +[[!template text="""but the box in the middle is the computer proper""" start="00:01:48.840" video="mainVideo-calc" id="subtitle"]] +[[!template text="""which has most of the components inside of it""" start="00:01:52.560" video="mainVideo-calc" id="subtitle"]] +[[!template text="""as well as the potentiometers for setting values,""" start="00:01:55.720" video="mainVideo-calc" id="subtitle"]] +[[!template text="""and an operation switch.""" start="00:02:00.200" video="mainVideo-calc" id="subtitle"]] +[[!template text="""There's a patch panel on the left""" start="00:02:02.040" video="mainVideo-calc" id="subtitle"]] +[[!template text="""for connecting the different integrators,""" start="00:02:04.400" video="mainVideo-calc" id="subtitle"]] +[[!template text="""amplifiers, multipliers, and so forth together.""" start="00:02:07.120" video="mainVideo-calc" id="subtitle"]] +[[!template text="""Then the output of the simulation is displayed""" start="00:02:11.320" video="mainVideo-calc" id="subtitle"]] +[[!template text="""on the oscilloscope on the right side,""" start="00:02:16.920" video="mainVideo-calc" id="subtitle"]] +[[!template text="""which is a digital oscilloscope.""" start="00:02:19.800" video="mainVideo-calc" id="subtitle"]] +[[!template text="""To be honest, I think that a talk about analog computing""" start="00:02:25.480" video="mainVideo-calc" id="subtitle"]] +[[!template text="""would be much more interesting""" start="00:02:28.440" video="mainVideo-calc" id="subtitle"]] +[[!template text="""than the talk that I'm about to give,""" start="00:02:30.200" video="mainVideo-calc" id="subtitle"]] +[[!template text="""but unfortunately that would be out of scope for EmacsConf.""" start="00:02:32.040" video="mainVideo-calc" id="subtitle"]] + +<div class="transcript-heading">[[!template new="1" text="""What is Calc?""" start="00:02:36.640" video="mainVideo-calc" id="subtitle"]]</div>[[!template text="""So instead I will talk about Emacs Calc,""" start="00:02:36.640" video="mainVideo-calc" id="subtitle"]] +[[!template text="""the digital calculator built into Emacs.""" start="00:02:39.920" video="mainVideo-calc" id="subtitle"]] +[[!template text="""Emacs Calc, while not being a replacement for software""" start="00:02:43.360" video="mainVideo-calc" id="subtitle"]] +[[!template text="""like GNU Octave, does have advanced calculator functionality""" start="00:02:47.520" video="mainVideo-calc" id="subtitle"]] +[[!template text="""that can be useful in engineering, electronics,""" start="00:02:51.480" video="mainVideo-calc" id="subtitle"]] +[[!template text="""or other technical applications. So I don't want to oversell it,""" start="00:02:55.040" video="mainVideo-calc" id="subtitle"]] +[[!template text="""but I think functionality-wise, Calc is somewhere in between""" start="00:03:00.760" video="mainVideo-calc" id="subtitle"]] +[[!template text="""what you'd expect of a decent scientific calculator""" start="00:03:06.480" video="mainVideo-calc" id="subtitle"]] +[[!template text="""and an advanced graphics calculator.""" start="00:03:12.240" video="mainVideo-calc" id="subtitle"]] +[[!template text="""So this talk I'll mention is not intended to be a tutorial""" start="00:03:23.940" video="mainVideo-calc" id="subtitle"]] +[[!template text="""but only a brief introduction to Calc.""" start="00:03:28.840" video="mainVideo-calc" id="subtitle"]] +[[!template text="""Please refer to the built-in Calc info manual""" start="00:03:33.840" video="mainVideo-calc" id="subtitle"]] +[[!template text="""for detailed instructions on how to complete operations.""" start="00:03:37.440" video="mainVideo-calc" id="subtitle"]] +[[!template text="""Turn off my volume here.""" start="00:03:46.740" video="mainVideo-calc" id="subtitle"]] +[[!template text="""The documentation for Emacs Calc is built-in,""" start="00:04:01.480" video="mainVideo-calc" id="subtitle"]] +[[!template text="""although on some distributions you may have to install""" start="00:04:05.720" video="mainVideo-calc" id="subtitle"]] +[[!template text="""the Emacs documentation separately for licensing reasons.""" start="00:04:10.440" video="mainVideo-calc" id="subtitle"]] +[[!template text="""Calc presents itself as a stack-based calculator""" start="00:04:24.480" video="mainVideo-calc" id="subtitle"]] +[[!template text="""where entries are dropped onto a stack""" start="00:04:28.600" video="mainVideo-calc" id="subtitle"]] +[[!template text="""and then an operation is performed on the stack entries.""" start="00:04:31.600" video="mainVideo-calc" id="subtitle"]] +[[!template text="""For example, I can drop 1.23 onto the stack,""" start="00:04:36.740" video="mainVideo-calc" id="subtitle"]] +[[!template text="""and then 8.56, and then multiply them together.""" start="00:04:42.900" video="mainVideo-calc" id="subtitle"]] + +<div class="transcript-heading">[[!template new="1" text="""calc-algebraic-entry""" start="00:04:54.280" video="mainVideo-calc" id="subtitle"]]</div>[[!template text="""It may present itself as a stack-based calculator,""" start="00:04:54.280" video="mainVideo-calc" id="subtitle"]] +[[!template text="""but indeed, Calc is also capable of accepting input""" start="00:05:01.560" video="mainVideo-calc" id="subtitle"]] +[[!template text="""in the more well-known algebraic format""" start="00:05:05.400" video="mainVideo-calc" id="subtitle"]] +[[!template text="""by using the calc-algebraic-entry command,""" start="00:05:07.740" video="mainVideo-calc" id="subtitle"]] +[[!template text="""which by default is bound to the apostrophe (') key.""" start="00:05:10.760" video="mainVideo-calc" id="subtitle"]] +[[!template text="""So you type the apostrophe key, enter the algebraic input,""" start="00:05:15.000" video="mainVideo-calc" id="subtitle"]] +[[!template text="""including parentheses as needed.""" start="00:05:19.760" video="mainVideo-calc" id="subtitle"]] +[[!template text="""For example, here's a calculation of the resonance frequency""" start="00:05:22.760" video="mainVideo-calc" id="subtitle"]] +[[!template text="""of a coil which has an inductance of 250 microhenries""" start="00:05:28.200" video="mainVideo-calc" id="subtitle"]] +[[!template text="""and 160 picofarads, taken from one of my electronics handbooks.""" start="00:05:35.040" video="mainVideo-calc" id="subtitle"]] +[[!template text="""The formula for that is 1 over 2 pi""" start="00:05:41.060" video="mainVideo-calc" id="subtitle"]] +[[!template text="""and then the square root of our inductance""" start="00:05:50.020" video="mainVideo-calc" id="subtitle"]] +[[!template text="""which is in this case 250 microfarads - excuse me, microhenries""" start="00:05:57.440" video="mainVideo-calc" id="subtitle"]] +[[!template text="""and then the capacitance is 160 picofarads.""" start="00:06:06.280" video="mainVideo-calc" id="subtitle"]] +[[!template text="""Small typo here.""" start="00:06:19.400" video="mainVideo-calc" id="subtitle"]] +[[!template text="""Now I need to evaluate that one more time,""" start="00:06:24.400" video="mainVideo-calc" id="subtitle"]] +[[!template text="""because pi is a symbol.""" start="00:06:26.640" video="mainVideo-calc" id="subtitle"]] +[[!template text="""I get about 800 kHz resonant frequency.""" start="00:06:30.920" video="mainVideo-calc" id="subtitle"]] + +<div class="transcript-heading">[[!template new="1" text="""calc-roll-down""" start="00:06:37.399" video="mainVideo-calc" id="subtitle"]]</div>[[!template text="""The command calc-roll-down,""" start="00:06:37.399" video="mainVideo-calc" id="subtitle"]] +[[!template text="""which by default is bound to the TAB key,""" start="00:06:41.680" video="mainVideo-calc" id="subtitle"]] +[[!template text="""will swap the top two stack entries,""" start="00:06:44.200" video="mainVideo-calc" id="subtitle"]] +[[!template text="""which is sometimes useful if you need to manipulate something""" start="00:06:47.920" video="mainVideo-calc" id="subtitle"]] +[[!template text="""that's further down the stack.""" start="00:06:51.560" video="mainVideo-calc" id="subtitle"]] +[[!template text="""So I can swap this around and say multiply by two""" start="00:06:57.000" video="mainVideo-calc" id="subtitle"]] +[[!template text="""and then put it back where it was.""" start="00:07:02.040" video="mainVideo-calc" id="subtitle"]] +[[!template text="""This command is also capable of rolling the entire stack.""" start="00:07:05.480" video="mainVideo-calc" id="subtitle"]] +[[!template text="""Say I want to shift them all around.""" start="00:07:14.040" video="mainVideo-calc" id="subtitle"]] +[[!template text="""This can be done by passing extra arguments""" start="00:07:18.900" video="mainVideo-calc" id="subtitle"]] +[[!template text="""to the calc-roll-down function.""" start="00:07:21.400" video="mainVideo-calc" id="subtitle"]] +[[!template text="""That's a little bit inconvenient to do manually,""" start="00:07:23.560" video="mainVideo-calc" id="subtitle"]] +[[!template text="""so in my init file, I defined here a key definition""" start="00:07:28.280" video="mainVideo-calc" id="subtitle"]] +[[!template text="""that passes in those arguments correctly.""" start="00:07:40.080" video="mainVideo-calc" id="subtitle"]] +[[!template text="""I attached this to shift-tab,""" start="00:07:45.760" video="mainVideo-calc" id="subtitle"]] +[[!template text="""so this way, I can roll the entire stack.""" start="00:07:49.180" video="mainVideo-calc" id="subtitle"]] +[[!template text="""Then I could change one entry here""" start="00:07:52.320" video="mainVideo-calc" id="subtitle"]] +[[!template text="""and then put it back where it was.""" start="00:07:56.160" video="mainVideo-calc" id="subtitle"]] +[[!template text="""So Calc does algebraic input.""" start="00:08:03.460" video="mainVideo-calc" id="subtitle"]] + +<div class="transcript-heading">[[!template new="1" text="""Advanced functions""" start="00:08:07.760" video="mainVideo-calc" id="subtitle"]]</div>[[!template text="""It also does advanced functions""" start="00:08:07.760" video="mainVideo-calc" id="subtitle"]] +[[!template text="""that you would expect any handheld scientific calculator,""" start="00:08:10.160" video="mainVideo-calc" id="subtitle"]] +[[!template text="""including trigonometric functions.""" start="00:08:15.600" video="mainVideo-calc" id="subtitle"]] +[[!template text="""For example, we can get the sine of a number.""" start="00:08:19.160" video="mainVideo-calc" id="subtitle"]] +[[!template text="""Now I'll mention here that Calc has multiple modes.""" start="00:08:25.320" video="mainVideo-calc" id="subtitle"]] +[[!template text="""Right now it's in degree mode.""" start="00:08:30.720" video="mainVideo-calc" id="subtitle"]] +[[!template text="""You can switch over to radian mode if you want.""" start="00:08:32.320" video="mainVideo-calc" id="subtitle"]] +[[!template text="""I'm going to put it back in degrees.""" start="00:08:38.160" video="mainVideo-calc" id="subtitle"]] +[[!template text="""Drop 12 degrees on the stack, and then get the sine of that.""" start="00:08:42.800" video="mainVideo-calc" id="subtitle"]] +[[!template text="""And then with the inverse sine function, I can put it back.""" start="00:08:49.800" video="mainVideo-calc" id="subtitle"]] + +<div class="transcript-heading">[[!template new="1" text="""Solving equations with calc-solve-for""" start="00:08:58.180" video="mainVideo-calc" id="subtitle"]]</div>[[!template text="""Calc also has the nifty ability to solve equations for you""" start="00:08:58.180" video="mainVideo-calc" id="subtitle"]] +[[!template text="""so long as the equation is not too complicated.""" start="00:09:07.520" video="mainVideo-calc" id="subtitle"]] +[[!template text="""This is using the calc-solve-for function.""" start="00:09:13.920" video="mainVideo-calc" id="subtitle"]] +[[!template text="""For example, we could enter in an equation algebraically,""" start="00:09:19.960" video="mainVideo-calc" id="subtitle"]] +[[!template text="""then run calc-solve-for, and we just have to tell it""" start="00:09:31.700" video="mainVideo-calc" id="subtitle"]] +[[!template text="""what variable we want to solve for. And there we go.""" start="00:09:36.680" video="mainVideo-calc" id="subtitle"]] +[[!template text="""We can do this manually as well""" start="00:09:41.000" video="mainVideo-calc" id="subtitle"]] +[[!template text="""just so you can see that we get the same result.""" start="00:09:43.200" video="mainVideo-calc" id="subtitle"]] + +<div class="transcript-heading">[[!template new="1" text="""Systems of equations""" start="00:09:54.720" video="mainVideo-calc" id="subtitle"]]</div>[[!template text="""Calc is also able to solve systems of equations.""" start="00:09:54.720" video="mainVideo-calc" id="subtitle"]] +[[!template text="""We can put more than one equation on the stack,""" start="00:09:57.960" video="mainVideo-calc" id="subtitle"]] +[[!template text="""and then solve for several variables.""" start="00:10:03.440" video="mainVideo-calc" id="subtitle"]] +[[!template text="""To give a technical example for this,""" start="00:10:08.960" video="mainVideo-calc" id="subtitle"]] +[[!template text="""I'll show you a resistor network scribble that I did recently.""" start="00:10:13.320" video="mainVideo-calc" id="subtitle"]] +[[!template text="""Hopefully you can see that. Basically,""" start="00:10:30.660" video="mainVideo-calc" id="subtitle"]] +[[!template text="""it's fairly simple, a pretty simple resistor network""" start="00:10:32.820" video="mainVideo-calc" id="subtitle"]] +[[!template text="""with 1 kilo ohm and 10 kilo ohm resistors,""" start="00:10:38.720" video="mainVideo-calc" id="subtitle"]] +[[!template text="""and using the loop methods, we are calculating the currents,""" start="00:10:42.160" video="mainVideo-calc" id="subtitle"]] +[[!template text="""the current in each loop, and then that current can be used""" start="00:10:48.960" video="mainVideo-calc" id="subtitle"]] +[[!template text="""to solve for the voltage of each individual resistor""" start="00:10:52.760" video="mainVideo-calc" id="subtitle"]] +[[!template text="""if we want to. So at the bottom there we have the equations""" start="00:10:58.840" video="mainVideo-calc" id="subtitle"]] +[[!template text="""that we come up with as we work through each loop.""" start="00:11:06.200" video="mainVideo-calc" id="subtitle"]] +[[!template text="""And I'm going to paste that into Calc.""" start="00:11:11.520" video="mainVideo-calc" id="subtitle"]] +[[!template text="""To save some time, I'm going to copy and paste that""" start="00:11:19.580" video="mainVideo-calc" id="subtitle"]] +[[!template text="""from my notes instead of typing it out.""" start="00:11:22.720" video="mainVideo-calc" id="subtitle"]] +[[!template text="""So we have two equations there on the stack""" start="00:11:34.260" video="mainVideo-calc" id="subtitle"]] +[[!template text="""in one stack entry. We run that calc-solve-for function again,""" start="00:11:38.260" video="mainVideo-calc" id="subtitle"]] +[[!template text="""and we tell it which variables we want to solve for.""" start="00:11:44.720" video="mainVideo-calc" id="subtitle"]] +[[!template text="""And voila! Those are our currents,""" start="00:11:49.900" video="mainVideo-calc" id="subtitle"]] +[[!template text="""which we can then use to get the voltages""" start="00:11:51.960" video="mainVideo-calc" id="subtitle"]] +[[!template text="""for the individual resistors.""" start="00:11:55.720" video="mainVideo-calc" id="subtitle"]] + +<div class="transcript-heading">[[!template new="1" text="""calc-find-root""" start="00:12:00.080" video="mainVideo-calc" id="subtitle"]]</div>[[!template text="""I'll just briefly mention""" start="00:12:00.080" video="mainVideo-calc" id="subtitle"]] +[[!template text="""that if Calc is not able to solve an equation""" start="00:12:02.000" video="mainVideo-calc" id="subtitle"]] +[[!template text="""with calc-solve-for,""" start="00:12:05.840" video="mainVideo-calc" id="subtitle"]] +[[!template text="""then you might be helped by another calc function""" start="00:12:07.780" video="mainVideo-calc" id="subtitle"]] +[[!template text="""called calc-find-root.""" start="00:12:10.280" video="mainVideo-calc" id="subtitle"]] +[[!template text="""This function basically does a manual search""" start="00:12:11.560" video="mainVideo-calc" id="subtitle"]] +[[!template text="""for a numerical solution to the equation.""" start="00:12:14.440" video="mainVideo-calc" id="subtitle"]] +[[!template text="""And there's the documentation page on that.""" start="00:12:30.200" video="mainVideo-calc" id="subtitle"]] + +<div class="transcript-heading">[[!template new="1" text="""Derivatives and integrals""" start="00:12:39.960" video="mainVideo-calc" id="subtitle"]]</div>[[!template text="""Calc can also solve or find derivatives of functions,""" start="00:12:39.960" video="mainVideo-calc" id="subtitle"]] +[[!template text="""at least the more straightforward functions.""" start="00:12:44.040" video="mainVideo-calc" id="subtitle"]] +[[!template text="""For a simple example,""" start="00:12:47.580" video="mainVideo-calc" id="subtitle"]] +[[!template text="""we can get the derivative of that""" start="00:12:49.840" video="mainVideo-calc" id="subtitle"]] +[[!template text="""with the derivative function.""" start="00:13:00.560" video="mainVideo-calc" id="subtitle"]] +[[!template text="""On the other hand, Calc is also capable of figuring out""" start="00:13:11.980" video="mainVideo-calc" id="subtitle"]] +[[!template text="""indefinite integrals.""" start="00:13:17.160" video="mainVideo-calc" id="subtitle"]] +[[!template text="""Say we put that function back on the stack,""" start="00:13:22.100" video="mainVideo-calc" id="subtitle"]] +[[!template text="""and this time, we call the integral function.""" start="00:13:26.860" video="mainVideo-calc" id="subtitle"]] +[[!template text="""There you go. Of course, you have to add""" start="00:13:32.560" video="mainVideo-calc" id="subtitle"]] +[[!template text="""your own constant of integration.""" start="00:13:35.080" video="mainVideo-calc" id="subtitle"]] +[[!template text="""For integrals that Calc cannot figure out symbolically,""" start="00:13:39.820" video="mainVideo-calc" id="subtitle"]] +[[!template text="""a numerical integration method is available""" start="00:13:43.400" video="mainVideo-calc" id="subtitle"]] +[[!template text="""through the calc-num-integral command, which is documented...""" start="00:13:46.080" video="mainVideo-calc" id="subtitle"]] +[[!template text="""The function documentation is available here, more or less.""" start="00:13:59.999" video="mainVideo-calc" id="subtitle"]] + +<div class="transcript-heading">[[!template new="1" text="""Programmable functions""" start="00:14:17.540" video="mainVideo-calc" id="subtitle"]]</div>[[!template text="""I definitely need to mention""" start="00:14:17.540" video="mainVideo-calc" id="subtitle"]] +[[!template text="""that Calc is capable of doing programmable functions.""" start="00:14:20.400" video="mainVideo-calc" id="subtitle"]] +[[!template text="""That is to say, you can program your own functions into Calc.""" start="00:14:24.760" video="mainVideo-calc" id="subtitle"]] +[[!template text="""There are three separate ways to do this.""" start="00:14:29.620" video="mainVideo-calc" id="subtitle"]] +[[!template text="""One is through a macro method""" start="00:14:32.240" video="mainVideo-calc" id="subtitle"]] +[[!template text="""similar to Emacs's usual keyboard macros.""" start="00:14:36.280" video="mainVideo-calc" id="subtitle"]] +[[!template text="""The second method is to transform an algebraic function""" start="00:14:41.540" video="mainVideo-calc" id="subtitle"]] +[[!template text="""into a stored function definition.""" start="00:14:46.520" video="mainVideo-calc" id="subtitle"]] +[[!template text="""And the third is to use Elisp directly.""" start="00:14:50.860" video="mainVideo-calc" id="subtitle"]] +[[!template text="""Personally, I find that the second method""" start="00:14:54.060" video="mainVideo-calc" id="subtitle"]] +[[!template text="""is the most practical, the most convenient and practical""" start="00:14:56.600" video="mainVideo-calc" id="subtitle"]] +[[!template text="""in my opinion. So I'll give a quick example of that.""" start="00:15:01.800" video="mainVideo-calc" id="subtitle"]] +[[!template text="""So I could... Let's say I wanted to have a function""" start="00:15:08.060" video="mainVideo-calc" id="subtitle"]] +[[!template text="""for calculating capacitive reactance.""" start="00:15:14.160" video="mainVideo-calc" id="subtitle"]] +[[!template text="""I'll define that in algebraic mode first.""" start="00:15:20.700" video="mainVideo-calc" id="subtitle"]] +[[!template text="""The function for that is 1 over 2 pi""" start="00:15:28.900" video="mainVideo-calc" id="subtitle"]] +[[!template text="""the frequency and the capacitance.""" start="00:15:33.640" video="mainVideo-calc" id="subtitle"]] +[[!template text="""Drop that on the stack. You see, it does automatically""" start="00:15:41.600" video="mainVideo-calc" id="subtitle"]] +[[!template text="""get simplified a little bit, but it's the same function.""" start="00:15:44.960" video="mainVideo-calc" id="subtitle"]] +[[!template text="""And then I press letters Z and F. Do that again.""" start="00:15:52.080" video="mainVideo-calc" id="subtitle"]] +[[!template text="""Z and F to start transforming that into a stored function.""" start="00:15:58.840" video="mainVideo-calc" id="subtitle"]] +[[!template text="""It asks me to select a user key, a single key press.""" start="00:16:06.240" video="mainVideo-calc" id="subtitle"]] +[[!template text="""I'll use the letter c.""" start="00:16:11.040" video="mainVideo-calc" id="subtitle"]] +[[!template text="""Then it's going to ask for a longer command name.""" start="00:16:15.480" video="mainVideo-calc" id="subtitle"]] +[[!template text="""I've actually defined this once before, so it prefilled in""" start="00:16:19.080" video="mainVideo-calc" id="subtitle"]] +[[!template text="""that command name.""" start="00:16:24.640" video="mainVideo-calc" id="subtitle"]] +[[!template text="""Then I need to enter which variables in the formula""" start="00:16:38.340" video="mainVideo-calc" id="subtitle"]] +[[!template text="""are actual arguments, rather than just symbols""" start="00:16:43.000" video="mainVideo-calc" id="subtitle"]] +[[!template text="""to be evaluated later. I prefer to put this in with frequency""" start="00:16:46.560" video="mainVideo-calc" id="subtitle"]] +[[!template text="""and the capacitance after that,""" start="00:16:52.560" video="mainVideo-calc" id="subtitle"]] +[[!template text="""but actually in this particular case,""" start="00:16:54.280" video="mainVideo-calc" id="subtitle"]] +[[!template text="""it doesn't matter at all to the mathematics.""" start="00:16:57.800" video="mainVideo-calc" id="subtitle"]] +[[!template text="""So, now all I have to do, that this is defined,""" start="00:17:07.340" video="mainVideo-calc" id="subtitle"]] +[[!template text="""is I can drop the frequency on the stack,""" start="00:17:11.400" video="mainVideo-calc" id="subtitle"]] +[[!template text="""which we'll say, for this example, will be 4.5 MHz,""" start="00:17:15.200" video="mainVideo-calc" id="subtitle"]] +[[!template text="""and then drop on the capacitance, which in this example""" start="00:17:24.400" video="mainVideo-calc" id="subtitle"]] +[[!template text="""will be 22 pF.""" start="00:17:32.280" video="mainVideo-calc" id="subtitle"]] +[[!template text="""Then I'll call the function that I just defined.""" start="00:17:40.320" video="mainVideo-calc" id="subtitle"]] +[[!template text="""I don't really like having to try to remember""" start="00:17:42.440" video="mainVideo-calc" id="subtitle"]] +[[!template text="""the short letters that I've come up with,""" start="00:17:45.240" video="mainVideo-calc" id="subtitle"]] +[[!template text="""so I'll just use the longer name.""" start="00:17:48.680" video="mainVideo-calc" id="subtitle"]] +[[!template text="""I need to evaluate one more time""" start="00:17:57.840" video="mainVideo-calc" id="subtitle"]] +[[!template text="""because the symbol pi is in there and not yet evaluated.""" start="00:17:59.800" video="mainVideo-calc" id="subtitle"]] +[[!template text="""And so if I've done that right,""" start="00:18:05.620" video="mainVideo-calc" id="subtitle"]] +[[!template text="""we have a capacitive reactance of about 1600 ohms.""" start="00:18:07.540" video="mainVideo-calc" id="subtitle"]] + +<div class="transcript-heading">[[!template new="1" text="""Plotting""" start="00:18:12.160" video="mainVideo-calc" id="subtitle"]]</div>[[!template text="""As the last feature that I'll mention here,""" start="00:18:12.160" video="mainVideo-calc" id="subtitle"]] +[[!template text="""Emacs Calc does have an interface with gnuplot,""" start="00:18:16.840" video="mainVideo-calc" id="subtitle"]] +[[!template text="""if you want to have Calc work as your graphing calculator.""" start="00:18:24.060" video="mainVideo-calc" id="subtitle"]] +[[!template text="""I do need to be honest and mention""" start="00:18:30.800" video="mainVideo-calc" id="subtitle"]] +[[!template text="""that I don't generally use it myself""" start="00:18:33.160" video="mainVideo-calc" id="subtitle"]] +[[!template text="""because there's another program in GNOME""" start="00:18:35.580" video="mainVideo-calc" id="subtitle"]] +[[!template text="""that I've found to be generally more convenient""" start="00:18:39.720" video="mainVideo-calc" id="subtitle"]] +[[!template text="""for the things that I want to graph quickly.""" start="00:18:43.500" video="mainVideo-calc" id="subtitle"]] +[[!template text="""But I think I can give you a simple example.""" start="00:18:47.400" video="mainVideo-calc" id="subtitle"]] +[[!template text="""So first, we need to drop a range on the stack.""" start="00:18:53.400" video="mainVideo-calc" id="subtitle"]] +[[!template text="""Let's say 0 to 10.""" start="00:19:00.340" video="mainVideo-calc" id="subtitle"]] +[[!template text="""And then we need to drop the function on the stack.""" start="00:19:06.620" video="mainVideo-calc" id="subtitle"]] +[[!template text="""And then I believe it's the letters g and f that graph this.""" start="00:19:11.640" video="mainVideo-calc" id="subtitle"]] +[[!template text="""Let's see. Yep, there we go.""" start="00:19:17.840" video="mainVideo-calc" id="subtitle"]] +[[!template text="""So there's our function and it looks nice.""" start="00:19:22.320" video="mainVideo-calc" id="subtitle"]] +[[!template text="""That was pretty easy.""" start="00:19:25.060" video="mainVideo-calc" id="subtitle"]] +[[!template text="""That's the fast way to do it.""" start="00:19:26.660" video="mainVideo-calc" id="subtitle"]] +[[!template text="""I will, as a disclaimer, mention that""" start="00:19:29.020" video="mainVideo-calc" id="subtitle"]] +[[!template text="""using this quick approach,""" start="00:19:32.840" video="mainVideo-calc" id="subtitle"]] +[[!template text="""that sometimes more complicated graphs""" start="00:19:34.160" video="mainVideo-calc" id="subtitle"]] +[[!template text="""will not turn out nicely,""" start="00:19:38.760" video="mainVideo-calc" id="subtitle"]] +[[!template text="""because by default, the resolution will be pretty low.""" start="00:19:40.000" video="mainVideo-calc" id="subtitle"]] +[[!template text="""That is to say it's... gnuplot is going to be""" start="00:19:44.340" video="mainVideo-calc" id="subtitle"]] +[[!template text="""skipping a lot of points""" start="00:19:48.120" video="mainVideo-calc" id="subtitle"]] +[[!template text="""and so you'll have to learn a bit more""" start="00:19:49.900" video="mainVideo-calc" id="subtitle"]] +[[!template text="""about how to use the interface,""" start="00:19:52.040" video="mainVideo-calc" id="subtitle"]] +[[!template text="""what parameters to pass if you want all your graphs""" start="00:19:55.320" video="mainVideo-calc" id="subtitle"]] +[[!template text="""to come out looking nice.""" start="00:19:59.520" video="mainVideo-calc" id="subtitle"]] +[[!template text="""So that covers all the features that I wanted to cover.""" start="00:20:03.700" video="mainVideo-calc" id="subtitle"]] + +<div class="transcript-heading">[[!template new="1" text="""Wish list""" start="00:20:08.800" video="mainVideo-calc" id="subtitle"]]</div>[[!template text="""I wanted to briefly mention a wish list of items""" start="00:20:08.800" video="mainVideo-calc" id="subtitle"]] +[[!template text="""that I'd like to see in Calc.""" start="00:20:13.280" video="mainVideo-calc" id="subtitle"]] +[[!template text="""One of them would be improper integrals.""" start="00:20:16.680" video="mainVideo-calc" id="subtitle"]] +[[!template text="""So that's like our definite integrals""" start="00:20:23.640" video="mainVideo-calc" id="subtitle"]] +[[!template text="""except for where a limit of integration is infinity.""" start="00:20:25.160" video="mainVideo-calc" id="subtitle"]] +[[!template text="""That's something that can be useful in a few applications.""" start="00:20:32.860" video="mainVideo-calc" id="subtitle"]] +[[!template text="""Something else that would be neat to have would be""" start="00:20:38.560" video="mainVideo-calc" id="subtitle"]] +[[!template text="""annotations for row entries. So for example""" start="00:20:41.080" video="mainVideo-calc" id="subtitle"]] +[[!template text="""if I was putting together a sum of numbers""" start="00:20:45.680" video="mainVideo-calc" id="subtitle"]] +[[!template text="""for, say, my monthly budget,""" start="00:20:48.820" video="mainVideo-calc" id="subtitle"]] +[[!template text="""let's say I was paying $2,000 for my rent""" start="00:20:53.280" video="mainVideo-calc" id="subtitle"]] +[[!template text="""and let's say $800 a month for my groceries,""" start="00:20:57.480" video="mainVideo-calc" id="subtitle"]] +[[!template text="""(a lot of kids to feed there)""" start="00:21:03.832" video="mainVideo-calc" id="subtitle"]] +[[!template text="""and then say another $60 for dining out, and so on,""" start="00:21:07.932" video="mainVideo-calc" id="subtitle"]] +[[!template text="""it would be nice if there was some way""" start="00:21:14.566" video="mainVideo-calc" id="subtitle"]] +[[!template text="""to put a little annotation next to each number""" start="00:21:18.260" video="mainVideo-calc" id="subtitle"]] +[[!template text="""so that you could remember""" start="00:21:21.320" video="mainVideo-calc" id="subtitle"]] +[[!template text="""what the meaning of that number was more easily.""" start="00:21:23.400" video="mainVideo-calc" id="subtitle"]] +[[!template text="""I actually looked into programming this into Calc myself,""" start="00:21:27.040" video="mainVideo-calc" id="subtitle"]] +[[!template text="""but discovered that it would require reprogramming""" start="00:21:31.200" video="mainVideo-calc" id="subtitle"]] +[[!template text="""quite a bit of Calc to make that work well""" start="00:21:35.920" video="mainVideo-calc" id="subtitle"]] +[[!template text="""across all calc functionality,""" start="00:21:41.840" video="mainVideo-calc" id="subtitle"]] +[[!template text="""and so, eventually, I gave up.""" start="00:21:43.480" video="mainVideo-calc" id="subtitle"]] +[[!template text="""But I'd still really like to have that feature.""" start="00:21:46.940" video="mainVideo-calc" id="subtitle"]] +[[!template text="""The final thing, though""" start="00:21:51.140" video="mainVideo-calc" id="subtitle"]] +[[!template text="""I think this would not necessarily belong in Calc,""" start="00:21:52.040" video="mainVideo-calc" id="subtitle"]] +[[!template text="""I think it would be cool if Emacs had some way""" start="00:21:54.580" video="mainVideo-calc" id="subtitle"]] +[[!template text="""to run numerical solutions""" start="00:21:57.920" video="mainVideo-calc" id="subtitle"]] +[[!template text="""for systems of differential equations,""" start="00:22:00.600" video="mainVideo-calc" id="subtitle"]] +[[!template text="""also known as a differential analyzer.""" start="00:22:02.600" video="mainVideo-calc" id="subtitle"]] +[[!template text="""So this would allow you to be able to set up simulation models""" start="00:22:06.020" video="mainVideo-calc" id="subtitle"]] +[[!template text="""involving systems of differential equations,""" start="00:22:09.280" video="mainVideo-calc" id="subtitle"]] +[[!template text="""for example, a spring mass system, or pressure temperature,""" start="00:22:11.680" video="mainVideo-calc" id="subtitle"]] +[[!template text="""or what have you, and then run the simulation""" start="00:22:14.880" video="mainVideo-calc" id="subtitle"]] +[[!template text="""using numerical approximation.""" start="00:22:18.040" video="mainVideo-calc" id="subtitle"]] +[[!template text="""Maybe it would be silly""" start="00:22:22.120" video="mainVideo-calc" id="subtitle"]] +[[!template text="""to actually put that in Calc itself,""" start="00:22:24.080" video="mainVideo-calc" id="subtitle"]] +[[!template text="""but a nice interface maybe to some other software,""" start="00:22:26.000" video="mainVideo-calc" id="subtitle"]] +[[!template text="""simple software that did that,""" start="00:22:30.340" video="mainVideo-calc" id="subtitle"]] +[[!template text="""an easy to use interface for that""" start="00:22:33.300" video="mainVideo-calc" id="subtitle"]] +[[!template text="""would be really great.""" start="00:22:35.780" video="mainVideo-calc" id="subtitle"]] + +<div class="transcript-heading">[[!template new="1" text="""Wrapping up""" start="00:22:38.600" video="mainVideo-calc" id="subtitle"]]</div>[[!template text="""So that's my entire talk.""" start="00:22:38.600" video="mainVideo-calc" id="subtitle"]] +[[!template text="""I'll just mention some information.""" start="00:22:41.801" video="mainVideo-calc" id="subtitle"]] +[[!template text="""If you want to learn more about me""" start="00:22:44.535" video="mainVideo-calc" id="subtitle"]] +[[!template text="""or things that I'm interested in,""" start="00:22:48.366" video="mainVideo-calc" id="subtitle"]] +[[!template text="""I do not any longer have a web presence.""" start="00:22:50.120" video="mainVideo-calc" id="subtitle"]] +[[!template text="""I don't have a website anymore,""" start="00:22:57.780" video="mainVideo-calc" id="subtitle"]] +[[!template text="""but I do have a Gemini capsule""" start="00:22:59.660" video="mainVideo-calc" id="subtitle"]] +[[!template text="""that I post to all the time.""" start="00:23:03.360" video="mainVideo-calc" id="subtitle"]] +[[!template text="""And if you can install, if you're willing to install the...""" start="00:23:07.140" video="mainVideo-calc" id="subtitle"]] +[[!template text="""Gemini browser known as Elpher""" start="00:23:13.880" video="mainVideo-calc" id="subtitle"]] +[[!template text="""into Emacs, which is available from ELPA,""" start="00:23:19.080" video="mainVideo-calc" id="subtitle"]] +[[!template text="""then you can browse directly to it""" start="00:23:23.699" video="mainVideo-calc" id="subtitle"]] +[[!template text="""and look around my Gemini capsule.""" start="00:23:27.360" video="mainVideo-calc" id="subtitle"]] +[[!template text="""Thank you very much.""" start="00:23:31.440" video="mainVideo-calc" id="subtitle"]] + +</div> + +Captioner: sachac + Questions or comments? Please e-mail [christopher@librehacker.com](mailto:christopher@librehacker.com?subject=Comment%20for%20EmacsConf%202023%20calc%3A%20Basic%20Calc%20functionality%20for%20engineering%20or%20electronics) diff --git a/2025/info/calc-before.md b/2025/info/calc-before.md index ae994a76..271d9d3f 100644 --- a/2025/info/calc-before.md +++ b/2025/info/calc-before.md @@ -8,12 +8,27 @@ The following image shows where the talk is in the schedule for Sat 2025-12-06. Format: 24-min talk ; Q&A: IRC <https://chat.emacsconf.org/?join=emacsconf,emacsconf-gen> Etherpad: <https://pad.emacsconf.org/2025-calc> Etherpad: <https://pad.emacsconf.org/2025-calc> Discuss on IRC: [#emacsconf-gen](https://chat.emacsconf.org/?join=emacsconf,emacsconf-gen) -Status: Ready to stream +Status: Now playing on the conference livestream <div>Times in different time zones:</div><div class="times" start="2025-12-06T18:00:00Z" end="2025-12-06T18:25:00Z"><div class="conf-time">Saturday, Dec 6 2025, ~1:00 PM - 1:25 PM EST (US/Eastern)</div><div class="others"><div>which is the same as:</div>Saturday, Dec 6 2025, ~12:00 PM - 12:25 PM CST (US/Central)<br />Saturday, Dec 6 2025, ~11:00 AM - 11:25 AM MST (US/Mountain)<br />Saturday, Dec 6 2025, ~10:00 AM - 10:25 AM PST (US/Pacific)<br />Saturday, Dec 6 2025, ~6:00 PM - 6:25 PM UTC <br />Saturday, Dec 6 2025, ~7:00 PM - 7:25 PM CET (Europe/Paris)<br />Saturday, Dec 6 2025, ~8:00 PM - 8:25 PM EET (Europe/Athens)<br />Saturday, Dec 6 2025, ~11:30 PM - 11:55 PM IST (Asia/Kolkata)<br />Sunday, Dec 7 2025, ~2:00 AM - 2:25 AM +08 (Asia/Singapore)<br />Sunday, Dec 7 2025, ~3:00 AM - 3:25 AM JST (Asia/Tokyo)</div></div><div><strong><a href="/2025/watch/gen/">Find out how to watch and participate</a></strong></div> +<div class="vid mainVideo"><video controls preload="none" id="mainVideo-calc"><source src="https://media.emacsconf.org/2025/emacsconf-2025-calc--basic-calc-functionality-for-engineering-or-electronics--christopher-howard--main.webm" />captions="""<track label="English" kind="captions" srclang="en" src="/2025/captions/emacsconf-2025-calc--basic-calc-functionality-for-engineering-or-electronics--christopher-howard--main.vtt" default />"""<track kind="chapters" label="Chapters" src="/2025/captions/emacsconf-2025-calc--basic-calc-functionality-for-engineering-or-electronics--christopher-howard--main--chapters.vtt" /><p><em>Your browser does not support the video tag. Please download the video instead.</em></p></video>[[!template id="chapters" vidid="mainVideo-calc" data=""" +00:03.620 Introduction +02:36.640 What is Calc? +04:54.280 calc-algebraic-entry +06:37.399 calc-roll-down +08:07.760 Advanced functions +08:58.180 Solving equations with calc-solve-for +09:54.720 Systems of equations +12:00.080 calc-find-root +12:39.960 Derivatives and integrals +14:17.540 Programmable functions +18:12.160 Plotting +20:08.800 Wish list +22:38.600 Wrapping up +"""]]<div></div>Duration: 23:35 minutes<div class="files resources"><ul><li><a href="https://pad.emacsconf.org/2025-calc">Open Etherpad</a></li><li><a href="https://chat.emacsconf.org/?join=emacsconf,emacsconf-gen">Open public Q&A</a></li><li><a href="https://media.emacsconf.org/2025/emacsconf-2025-calc--basic-calc-functionality-for-engineering-or-electronics--christopher-howard--intro.vtt">Download --intro.vtt</a></li><li><a href="https://media.emacsconf.org/2025/emacsconf-2025-calc--basic-calc-functionality-for-engineering-or-electronics--christopher-howard--intro.webm">Download --intro.webm</a></li><li><a href="https://media.emacsconf.org/2025/emacsconf-2025-calc--basic-calc-functionality-for-engineering-or-electronics--christopher-howard--main--chapters.vtt">Download --main--chapters.vtt</a></li><li><a href="https://media.emacsconf.org/2025/emacsconf-2025-calc--basic-calc-functionality-for-engineering-or-electronics--christopher-howard--main.opus">Download --main.opus (20MB)</a></li><li><a href="https://media.emacsconf.org/2025/emacsconf-2025-calc--basic-calc-functionality-for-engineering-or-electronics--christopher-howard--main.png">Download --main.png</a></li><li><a href="https://media.emacsconf.org/2025/emacsconf-2025-calc--basic-calc-functionality-for-engineering-or-electronics--christopher-howard--main.vtt">Download --main.vtt</a></li><li><a href="https://media.emacsconf.org/2025/emacsconf-2025-calc--basic-calc-functionality-for-engineering-or-electronics--christopher-howard--main.webm">Download --main.webm (56MB)</a></li><li><a href="https://youtu.be/MAc6gCUHjOw">View on Youtube</a></li></ul></div></div> # Description <!-- End of emacsconf-publish-before-page -->
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