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constant time cadence [message #94361]

Thu, 20 April 2017 03:39

gunvicsin11
Messages: 93
Registered: November 2012

Member

Hi all,
I have a set of data with time cadence of 6s , 7s , 8s sometimes 11s, 80s, 300s like that. But I want them to be of constant 360s time cadence. How can I do that, anybody have idea.
thanks

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Re: constant time cadence [message #94362 is a reply to message #94361]

Thu, 20 April 2017 05:46

natha
Messages: 482
Registered: October 2007

Senior Member

Interpolation (see function interpol) or nearest neighbor. Example:

n=10
new_data=replicate(!values.f_nan,n)
new_time=lindgen(n)*300L

for i=0L, n-1 do begin
dist=min(abs(your_time - new_time[i]),pos)
if dist lt 5 then new_data[i]=your_data[pos]
endfor

In this example "your_time" and "your_data" are you arrays. Note that I set a tolerance of 5 seconds, you could change that...

Using interpol, would be something like:

new_data=interpol(your_data,your_time,new_time)

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Re: constant time cadence [message #94363 is a reply to message #94361]

Thu, 20 April 2017 05:46

Matthew Argall
Messages: 286
Registered: October 2011

Senior Member

Via interpolation.

;Create sample time and data arrays
time = [0:720:6]
time = [time, [time[-1] + 7:time[-1]+728:7] ]
time = [time, [time[-1] + 8:time[-1]+728:8] ]
time = [time, [time[-1] + 11:time[-1]+770:11] ]
time = [time, [time[-1] + 80:time[-1]+800:80] ]
time = [time, [time[-1] + 300:time[-1]+900:300] ]
data = FIndGen( N_Elements(time) )

;Create desired time cadence and interpolate data
tout = [time[0]:time[-1]:360.0]
dout = Interpol(data, time, tout)

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Re: constant time cadence [message #94364 is a reply to message #94361]

Thu, 20 April 2017 05:58

lecacheux.alain
Messages: 325
Registered: January 2008

Senior Member

Le jeudi 20 avril 2017 12:39:19 UTC+2, sid a écrit :
> Hi all,
> I have a set of data with time cadence of 6s , 7s , 8s sometimes 11s, 80s, 300s like that. But I want them to be of constant 360s time cadence. How can I do that, anybody have idea.
> thanks

new_data = INTERPOLATE(data, INTERPOL(dindgen(times.length), times, new_times)

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Re: constant time cadence [message #94365 is a reply to message #94361]

Thu, 20 April 2017 05:59

lecacheux.alain
Messages: 325
Registered: January 2008

Senior Member

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Re: constant time cadence [message #94366 is a reply to message #94361]

Fri, 21 April 2017 00:21

gunvicsin11
Messages: 93
Registered: November 2012

Member

On Thursday, April 20, 2017 at 4:09:19 PM UTC+5:30, sid wrote:
> Hi all,
> I have a set of data with time cadence of 6s , 7s , 8s sometimes 11s, 80s, 300s like that. But I want them to be of constant 360s time cadence. How can I do that, anybody have idea.
> thanks

Thanks everyone for the help, But I dont want to do interpolation. Its ok if I have approximately 360s. I need to addup the time cadence and bring to approximately 360s. How can I do this automatically.

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Re: constant time cadence [message #94367 is a reply to message #94366]

Fri, 21 April 2017 05:42

natha
Messages: 482
Registered: October 2007

Senior Member

Use my nearest neighbor code

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