Window length in bz_FindRipples.m

[37ig]

Hi,

I'm a bit confused about how the RMS window length is computed in bz_FindRipples.m

Lines 132 reads: windowLength = frequency/frequency*11;

Which should always set the windowLength to 11 data-points. Is this as intended or an error?

Thanks for any help!

[brendonw1]

That is strange. That line is very odd and may even always result in a value of 11 (? depending on order of operations). I am cc'ing Antonio and David in case they might know more. I've almost never used that code and definitely didn't significantly write any of it Brendon Brendon Watson, MD-PhD Assistant Professor in Psychiatry Biomedical Sciences Research Building, Room 5059 University of Michigan 109 Zina Pitcher Place Ann Arbor, MI 48109-5720 Lab Website: http://watsonneurolab.org Clinical phone: 734-764-0231 <http://voice.google.com/calls?a=nc,%2B17347640231>

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On Wed, Dec 28, 2022 at 4:12 PM 37ig ***@***.***> wrote: Hi, I'm a bit confused about how the RMS window length is computed in bz_FindRipples.m Lines 132 reads: windowLength = frequency/frequency*11; Which should always set the windowLength to 11 data-points. Is this as intended or an error? Thanks for any help! — Reply to this email directly, view it on GitHub <#418>, or unsubscribe <https://github.com/notifications/unsubscribe-auth/AA26WTNFEQMF74SD22EPCM3WPSUIVANCNFSM6AAAAAATLSBNF4> . You are receiving this because you are subscribed to this thread.Message ID: ***@***.***>

[37ig]

Yes the order of operations means it does return 11. With a bit more investigation it looks like the bz_FindRipples.m may have been inspired by (or vice versa) the FMAToolbox function FindRipples.m.

The line in the FMAToolbox function is
windowLength = round(frequency/1250*11);
which makes much more sense. But would be useful if someone could confirm this please.

Cheers!

[dlevenstein]

This should absolutely be

windowLength = round(frequency/1250*11);

not sure when it got changed, or who's using that code rn - anyone?

[dlevenstein]

actually - I bet what happened is someone wanted to change the 1250 to be the sampling frequency from the sessionInfo, and then got messed up between the frequency of the filter vs the sampling frequency....

[evilrobotxoxo]

IMO this should be written as round(11 * frequency/1250) because under PEMDAS frequency/1250*11 is equal to frequency/(1250*11), but under BODMAS it's equal to (frequency/1250)*11 We should avoid that sort of ambiguity.

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On Fri, Jan 6, 2023 at 1:19 PM Dan Levenstein ***@***.***> wrote: actually - I bet what happened is someone wanted to change the 1250 to be the sampling frequency from the sessionInfo, and then got messed up between the frequency of the filter vs the sampling frequency.... — Reply to this email directly, view it on GitHub <#418 (comment)>, or unsubscribe <https://github.com/notifications/unsubscribe-auth/ABG4WJN56ITK4Q3HAI34S4DWRBO2HANCNFSM6AAAAAATLSBNF4> . You are receiving this because you are subscribed to this thread.Message ID: ***@***.***>