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Operation with units: f is not defined
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Hello, I am getting the following:  Basile
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Hi Basile.
That's is the expected way to work with smath.
To get the value of X.C you must to call the function after defining X.C with X.C(f)=
Best regards.
Alvaro.
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Alvaro,
Look to the left the of X.C , the X.L
Should behave the same?
Basile
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Originally Posted by: Basile  Alvaro,
Look to the left the of X.C , the X.L
Should behave the same?
Basile Depending which version, it could be. I guess that must to be an election from author, this is, if eval functions in that way. The "not evaluation" option, as the attached picture, it's ok for me. Best regards.  Alvaro.
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i am using  Basile
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Same problem as before: you have no circuit, then no LC project.
The only thing you can do is calculate the resonance frequency: 'fo'
Then plot it as sin(fo)
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Jean,
I am calculating the reactance of the inductor and the capacitor at a frequency f.
Basile
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In my times, pure L, C were strictly imaginary. Just by themselves they don't have much use
whereas there is no such thing as pure L , pure C. They both have physical resistiviy.
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Jean,
You are right that:
X.L=jωL
and
X.C=-j(1/ωC)
and the magnitude is that I calculate.
You can simply consider ideal elements without the loss resistance.
Basile
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Hi Basile. That's isn't.
Correct XL and XC (reactances) are without j, as in your worksheets.
ZL and ZC (impedances) are with j.
Actually the total impedance is Z = R + jX, where X = XL + XC is the total reactance.
Best regards.
Alvaro.
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Alvaro,
You are confusing things.
What you say are correct but have to do nothing to do with the question.
X.L, X.C are reactance (with j or without j)
Z is impedance of R and X.
Basile
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Originally Posted by: Basile Alvaro,
You are confusing things.
What you say are correct but have to do nothing to do with the question.
X.L, X.C are reactance (with j or without j)
Z is impedance of R and X.
Basile Hi Basile. I don't confusing. Reactances ( https://en.wikipedia.org/wiki/Electrical_reactance ) are reals and impedances ( https://en.wikipedia.org/wiki/Electrical_impedance ) are complexes. So X.L, X.C can't have j. About the numerical evaluation for a function, check this old post: http://en.smath.info/for...nction-as-a-program.aspx In X.L, X.C definitions as functions, f must to be a local variable. X.L(f) -> (symb evaluation) must to set the answer with "f", not with "100 Hz". And the numerical evaluation X.L(f) = must to be in red, as f as local variable isn't defined. As a choice of the program writer, and what you can see in the last post of the above referenced, you can set all the local variables as globals with f(x) = 1*(line ... ). Actually I'm not comfortable with that behavoir, but is the choice of Andrei. Best regards. Alvaro.
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Just like this Basile, for a family of "C's" at a fixed frequency 8 the magenta line. On the plot, 'f' => 'x'. 
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Jean, Yes, I can plot X.C(f) and X.L(f) but if I try to plot the difference or take the aritmetic difference does not work. Please see figure and figure in post #1 on top, if it helps.  Basile
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Basile, let's make it clear on three points: 1. You have no work sheet, then there is no project [no help]. 2. Read this link again https://en.wikipedia.org/wiki/LC_circuitto help you start onstruct a project. 3. Those gyzmas: they do nothing circuit wise. Jean 
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Jean, Attached please find the file.  test resonance.sm (8kb) downloaded 22 time(s).Basile
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Note that I have removed the unit system because
"Units don't match" error mesage ... so: zap !
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Jean,
"why units do not match? Are they both Ω?"
Basile
PS: Thank you for the discussion.
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Redefining subtraction or function.  Best Regards Carlos test resonance_CBG.sm (11kb) downloaded 14 time(s).
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