[SciPy-User] Filter problem

[Balachandar]

Hello, I am a newbie in Scipy and also to filtering. I have a data from a
pressure sensor. It needs to be filtered. The graph can be seen from the
attachment. The top one is unfiltere and the bottom one is filtered. As you
can see the shape looks the same. I need a good smooth line. My code goes
like this..

b,a = butter(10, 0.2, 'low')
    ICPfiltered = lfilter(b,a,ICPunfiltered)

where ICPfiltered is the filtered value and ICP unfiltered is the data from
the sensor. Its a 1-dimensional array. Am i doing anything wrong with the
usage of the api's. I have tried to change the cut
-off frequency also but it isn't  of any use. Should i use any other filter
other than butterworth iir to get a smooth curve. Thank you....

Thanks,
Bala
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