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Voltage Divider: Solve for Missing Variable
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You have defined R2, maybe that's why you can't solve. First you need to be sure calculation variable cleared. And if you defined your function, it will also prevent the solution. Some remembrance for smath solvers; solve(), roots() and al_nleqsolve() won't work directly with units. You have to trick them for units, adding into equations. Maple solve and FindRoot() can work with units. I also included mathblock method, which relies on FindRoot(). If your root is beyond -20,20 you have to specify it for roots() and solve(). Unless you didn't already change Root Ranges in options. And you also have to guess a starting point for FindRoot(). Regards 20220408 Voltage Divider Solve_v2.sm (51kb) downloaded 13 time(s).
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Originally Posted by: marks2c I've been unable to solve this Make it SI ...
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Originally Posted by: Jean Giraud Make it SI ... That kΩ is not an SI unit you clown. It is simply equal to 1, not (kg*m^2)/(A^2*s^3).
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Originally Posted by: overlord That kΩ is not an SI unit
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Originally Posted by: marks2c Resistive Voltage Divider Solve for R2 (or any variable) Greetings Mark, For your first part, you can copy and paste this formula (solved for R2): Code:R2:{R1*V.out}/{V.in-V.out}
For your second part, please reference the following forum topic: https://en.smath.com/for...quations-with-Solve.aspxThere is a healthy discussion of various methods to solve for an unknown variable. Hope that Helps! -Kenny Lemens, P.E. |
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Originally Posted by: Jean Giraud Your kΩ is not SI unit dumbass, which has value of 1. The one you have defined as 1, that you wrote kΩ:1. SMath kΩ of course is a SI unit, not your goofer kΩ. If you claim your kΩ is suitable to SI, just share us the multiplication of "your" kΩ with A^2. A is Ampere if I could help your unitless brain. For your information, result is kW. I will just wait your gibberish reply and answer it with a new insult.
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Originally Posted by: marks2c I've been unable to solve this As well, maple will solve. Maple is unit-less. Smath w/o maple is missing the best, particularly in Process Control & Instrumentation. Why not a new thread for your Thermodynamic/Chemical project. Cherrs ... Jean.
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Thank you all so much. The help is very greatly appreciated. Mark
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Originally Posted by: Kenny Lemens Originally Posted by: marks2c Resistive Voltage Divider Solve for R2 (or any variable) Greetings Mark, For your first part, you can copy and paste this formula (solved for R2): Code:R2:{R1*V.out}/{V.in-V.out}
... Hope that Helps! -Kenny Lemens, P.E. Thank you so much Kenny. The direct 'no solving required' approach is perfect. Again, thank you. Mark
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Originally Posted by: Jean Giraud Of course NOT ! Of course it is, even your example can solve with SI units. If you were not a duffer and enter units as they should be, you would witness the miracle. Look Jean. No magic numbers, no conversion factors, only numbers and units. Units can easily be shown in their kilo, mega, centi, mili form by using SI. Declaring them as 1 or creating same name units is just pure stupidity. I get it, you learn to calculate when units are not a thing for softwares back then. But time is changed. Softwares have unit supports now, it is the correct path to use units. You simply resist to learn new things, in every situation, and encourage your ignorance to new users. Which means you don't have primer feature of a scientist or engineer.
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Rank: Advanced Member Groups: Registered, Advanced Member Joined: 10/11/2010(UTC) Posts: 1,494 Was thanked: 1274 time(s) in 745 post(s)
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To be completely honest, I helped Maple understand units. The plugin uses the old 6th version of the program, and support for units appeared in the 7th version. |
Russia ☭ forever Viacheslav N. Mezentsev |
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About that long discussion Si and Solve, you can get lot more solving on the canvas. Willing difficult Titration, more convivial Pitot. Cheers ... Jean. By same token: thanks Viacheslav for maple/Units Titration.sm (27kb) downloaded 8 time(s).
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Originally Posted by: uni To be completely honest, I helped Maple understand units. The plugin uses the old 6th version of the program, and support for units appeared in the 7th version. Thanks for the unit support. So original maple has unit support since 2001. And smath maple plugin has also unit support, that is what concerns us, which proves Jean is wrong again.
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Rank: Advanced Member Groups: Registered, Advanced Member Joined: 10/11/2010(UTC) Posts: 1,494 Was thanked: 1274 time(s) in 745 post(s)
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Originally Posted by: overlord Thanks for the unit support. Originally Posted by: uni Updated (maple()). Fixed issue with trigonometric functions, added support for units. A post about this can be found here. And how it works: In Maple units are passed as undefined variables wrapped in single quotes. Therefore, in fact, the SMath does all the work with units. This happens implicitly. But Maple can also work with them, as with symbolic variables. Edited by user 10 April 2022 10:18:07(UTC)
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Russia ☭ forever Viacheslav N. Mezentsev |
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Originally Posted by: overlord Thanks for the unit support. So original maple has unit support since 2001. And smath maple plugin has also unit support, that is what concerns us, which proves Jean is wrong again Viacheslav can confirm the date maple/Units.
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Rank: Advanced Member Groups: Registered
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Originally Posted by: overlord So original maple has unit support since 2001. Smath first version 2006_11_13 Mathcad 8 Pro, 11 is a Maple subcontract. May be old collab Alvaro can confirm maple 2001 supported units ?
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