0
$\begingroup$

I'm facing a problem with Manipulate here, It just plots a blank xy-axis. 

Manipulate[
  Plot[FourierTrigSeries[-x^2 + a x, x, 10], {x, -2 Pi, 2 Pi}], 
  {a, -10, 10}]
Improve this question
$\endgroup$
2
  • 3
    $\begingroup$ You need to add Evaluate[]: Plot[Evaluate[FourierTrigSeries[(* stuff *)], (* stuff *)] $\endgroup$ – J. M.'s ennui♦ Oct 1 '18 at 19:18
  • $\begingroup$ i didn't understand, what does evaluate do in this case? $\endgroup$ – hcp Oct 1 '18 at 19:23
4
$\begingroup$

J.M.'s advice, given in his comment, is one solution. Here is another using the plot option Evaluated. I also add custom x-axis ticks and give the option Appearance -> "Labeled" to the control variable a to make the manipulation more user friendly.

Manipulate[
  Plot[FourierTrigSeries[-x^2 + a x, x, 10], {x, -2 Pi, 2 Pi},
    Ticks -> {Subdivide[-2 Pi, 2 Pi, 8], Automatic},
    Evaluated -> True],
  {a, -10, 10, .2, Appearance -> "Labeled"}]

demo

Improve this answer
$\endgroup$

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

Not the answer you're looking for? Browse other questions tagged or ask your own question.