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From: Tim Rentsch <tr.17687@z991.linuxsc.com>
Newsgroups: comp.lang.c
Subject: Re: you think rust may outthrone c?
Date: Sat, 05 Aug 2023 06:09:44 -0700
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Xref: csiph.com comp.lang.c:171683

Kaz Kylheku <864-117-4973@kylheku.com> writes:

> On 2023-08-04, Tim Rentsch <tr.17687@z991.linuxsc.com> wrote:
>
>>     typedef unsigned long Index;
>>
>>     void
>>     convolve(
>>         float *out, const float *in, Index N, const float *filter, Index Nf
>>     ){
>>         Index i, j;
>>
>>         for(  i = 0;  i < N;  i++  ){
>>             float t = 0;
>>             for(  j = 0;  j < Nf;  j++  ){
>>                 Index k = i + j - Nf/2;
>>                 if(  k >= N  )  continue;
>>                 t += in[k] * filter[j];
>>             }
>>             out[i] = t;
>>         }
>>     }
>
> This looks like a (cross-)correlation, [...]

The key property is that it performs the same computation
as what seemed to be the intent of the original code.