Re: [myhdl-list] _Waiter.diff [was: intbv.saturate, intbv.wrap]

[Christopher L. F. <chr...@gm...>]

>
>> This would compare using '=='. Thomas has proposed to replace
>> this with 'is' test. I still don't really see what difference
>> this would make. Can you explain issue/error that you
>> are seeing?

> I proposed to remove the tuple because there is a problem with numpy
> comparison.
> This is a short test on the interactiv shell.
>
> ===============================================
>>>> a=[1,2]
>>>> b=[4,5]
>>>> a in b
>   = False
>>>> from numpy import arange
>>>> a = arange(3)
>>>> a in b
> ---------------------------------------------------------------------------
> ValueError                                Traceback (most recent  
> call last)
>
> ValueError: The truth value of an array with more than one element is
> ambiguous.
>  Use a.any() or a.all()
> =================================================

I had not realized that this error was only for numpy arrays as the  
example Thomas provided demonstrates.  I had originally thought this  
would have failed for a list as well.  Is this an issue/error with the  
numpy array?

Here is the snippet of code that I am using that fails.

  @instance
     def stimulus():
         """
         The following is a basic testbench to stimulate the CIC filter
         and create some plots.
         """

         yield clk.posedge
         rst.next = True
         yield delay(10)
         rst.next = False
         yield delay(10)

         for ii in range(Nloops):
             for jj in range(Nfft):
                 x.next = int(L * uniform(-1, 1))
                 xs[jj] = float(x)/L

                 ysave[jj] = float(y._val)/L  # Undo fix-point
                 yield clk.negedge

             favg = favg + abs(fft(ysave, Nfft)) / Nfft
             xfavg = xfavg + abs(fft(xs))/Nfft

         favg = favg / Nloops
         xfavg = xfavg / Nloops