Hello,
I am trying to plot this simple Fourier integral in Maxima 5.17.1:
(%i1) display2d : false$
(%i2) f(k):=integrate(exp(%i*k*x)*sin(x)/x,x,minf,inf)$
(%i3) [f(0), f(1), f(3/2)];
(%o3) [%pi,%pi,0]
So far so good.
(%i4) plot2d(f,[x,-3,3]);
(%o4)
(%i5) Warning: empty y range [0:0], adjusting to [-1:1]
Theoretically, f(k) must be equal to %pi for k in [-1;1] and 0
outside. The plot does not show anything in [-1;1].
Moreover, if I try this plotting command
plot2d(f(k),[k,-3,3]);
I get a stupid question about the sign of k-1.
Can anyone explain what is wrong here?
--
Stanislav