Hi,
I agree with you.

Comparing the outputs of
suvibro f1=0.5 f2=0.5 | suxgraph style=normal width=1500 title=normal
suvibro f1=0.5 f2=0.5 | suop of=diff | suxgraph style=normal width=1500 title=normal

it looks like there is an absolute value somewhere in the data flow. Notice that abs is the default option. So, I suspect a bug....

The code needs to be checked.
D.

On 04/11/2020 17:16, vld3 wrote:

Hello everyone

I would like to apply a derivative to a signal. 
I made a test with a simple cosine (created with suvibro) applying suop op=diff ... but I didn't get a sine. Why? 
thanks in advance

-- luca

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|Dominique Rousset           LFCR UMR5150 / E2S UPPA / Dpt des géosciences| 
|Univ. Pau et des Pays de l'Adour BP 1155       F-64013 Pau Cedex - France|
|mailto:dominique.rousset@univ-pau.fr jami:drousset http://lfc.univ-pau.fr|
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