CAS fourier_an ...

17012016, 02:38 PM
Post: #1




CAS fourier_an ...
Hello friends,
I try to use the new Funktion "fourier_an", "..._bn" or "..._cn" on CAS. The function I try to approximate is a rectangle signal. T=10ms f(x)= 10V = û a=0 n=1...6 In CAS: fourier_bn(Expr,Var,T,n,a) so I type fourier_bn(10,x,10,1,0) for b1 Normally the result is: b1=û*2/PI=20/PI b2=0 b3=û*2/(3*PI)=20/(3*PI) b4=0 b5=û*2/(5*PI)=20/(5*PI) b6=0 a0=û/2=5 But with HP Prime calculator: b1=b2=b3=b4=b5=b6=0 a0=10 The results are compleately wrong!!! Is there a mistake in using the function on my side or is it an bug? Thank you in advance for your help. REF 

18012016, 06:06 PM
Post: #2




RE: CAS fourier_an ...
Hi!
I assume that your function has a value of 10 V for the first 10 ms, and 0 V for the next 10 ms; in that case the period is 20 ms. So, if you use fourier_an() and fourier_bn() with a function whose value is: 10 if x<10, and 0 if x>=10, and use 20 as the period, you'll get the correct answer. a0=5 b1=20/PI b2=0 b3=20/(3*PI) ... 

13042016, 09:43 PM
Post: #3




RE: CAS fourier_an ...
Can you show me how to type in?
fourier_an(10,x,20,0,0) fourier_bn(10,x,20,1,0) . . . Is this right? REF (18012016 06:06 PM)JMB Wrote: Hi! 

29042016, 05:46 PM
(This post was last modified: 01052016 11:49 AM by JMB.)
Post: #4




RE: CAS fourier_an ...  
27092016, 09:14 PM
Post: #5




RE: CAS fourier_an ...  
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