On 07/29/2019 12:30 PM, Ellie White
wrote:
Hi Marcus,
If you look at lines 34 and 39, I think you will see that I
did consider the values for y. I've reattached the program
here in case I originally attached an older / incorrect
version. Let me know if you still see a problem. Thanks!
E.
It looks like you're plotting the squares of the means, instead of
the mean of the squares. Which will be very very different values.
Computing the arithmetic mean of a series of voltage samples doesn't
really give you anything useful, since they'll be (to a first
approximation)
uniformly distributed around zero, with a slight DC offset in one
direction or another.
On Mon, Jul 29, 2019 at 12:19
PM Marcus D. Leech < address@hidden>
wrote:
On
07/29/2019 08:22 AM, Ellie White wrote:
> Hi Marcus,
>
> Thanks for the interesting tidbit -- and yes, I'll be
following your
> advice on using the integrated block for sure. And by the
way -- I've
> got one more question on a similar theme as the previous
one. I
> modified my flowgraph again (attached), and am now saving
two data
> streams -- real and imaginary -- to two separate data
files and
> processing them using the attached python program. In the
python
> program, I am performing the same conversion as the
Complex to Mag^2
> Block, but yet again I am getting different answers from
what I expect
> (on the order of 10^-5 instead of ~0.01). Do you have any
suggestions
> as to what could be causing the difference I am seeing? I
am wondering
> if it has something to do with Python's handling of the
different IO
> types, but could definitely be wrong on that. Any advice
is much
> appreciated!
>
> Thanks Marcus! Take care,
> Ellie
>
Looks like your python program isn't squaring the real and
imaginary
components -- the values for "y" are never considered in your
program :)
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