# obspy-users Digest, Vol 73, Issue 2

**URL:** <https://discourse.obspy.org/t/obspy-users-digest-vol-73-issue-2/581>\
**Category:** Users Mailing List Archive\
**Tags:** archive\
**Created:** [December 5, 2016, 12:31pm UTC](https://discourse.obspy.org/t/obspy-users-digest-vol-73-issue-2/581 "2016-12-05T12:31:20Z")\
**Posts on this page:** 1\
**Page:** 1

<div class="post-metadata">

**Author:** ![Roberto\_Cabieces\_Dia](https://discourse.obspy.org/letter_avatar_proxy/v4/letter/r/e480ec/32.png) [@Roberto\_Cabieces\_Dia](https://discourse.obspy.org/u/Roberto_Cabieces_Dia)\
**Post date:** [December 5, 2016, 12:31pm UTC](https://discourse.obspy.org/t/obspy-users-digest-vol-73-issue-2/581/1 "2016-12-05T12:31:20Z")

</div>

Hello Martin Gal and the rest of obspy users,

First of all thank you so much for your rapid response.

1. Comments of the array,

The mean depth value of this deployment is at 4800 m, ant the data I will finally try to handle is going to be treated to avoid “tilt noise” and the microseism noise", so my idea is to reduce the overall noise to a good snr level.

As you told me I’ve been trying to plot my array response by using array\_transff\_freqslowness(), but something is wrong when i try to draw it.(I ve attach my script). So in your last email did you suggest that I have to plot ( sx,sy) plot and the module(s) versus frecuency right? do you have any example??

1. Another good question.

there is some way in obspy to make stack, to get a beamforming seismogram ( I mean to, I have the 5 seismograms and I would like to get the coherent sum of that), this is because in the example [https://docs.obspy.org/tutorial/code\_snippets/beamforming\_fk\_analysis.html](https://docs.obspy.org/tutorial/code_snippets/beamforming_fk_analysis.html), it show a kind of vespagram more than a beamforming seismogram.

Script

import numpy as np  
import matplotlib.pyplot as plt  
from [obspy.imaging.cm](http://obspy.imaging.cm) import obspy\_sequential  
from obspy.signal.array\_analysis import array\_transff\_freqslowness

# generate array coordinates

coords = np.array([[-10.373608,35.909685, 0.021], [-10.554655,35.594688, 0.154], [-10.988262,35.595025,0.023],[-10.988500, 36.220166,0.204], [-10.555266,36.220216,0.003]])  
#coords /= 1000.

#Slowness units are in s/m ¿this is right)

#frecuency units are in Hz, limit sample frecuency/2

slim= 0.001  
sxmin = -slim  
sxmax = slim  
symin = -slim  
symax = slim  
sstep = slim / 100.  
flim = 25  
fstep= flim / 100.  
fmax=flim  
fmin=0  
array\_transff\_freqslowness(coords, slim, sstep, fmin, fmax, fstep,coordsys=‘lonlat’)  
plt.pcolor(np.arange(sxmin, sxmax + sstep \* 1.1, sstep) - sstep / 2.,  
np.arange(symin, symax + sstep \* 1.1, sstep) - sstep / 2.)  
plt.colorbar()  
plt.clim(vmin=0., vmax=1.)  
plt.xlim(sxmin, sxmax)  
plt.ylim(symin, symax)  
plt.show()

I am very grateful for anyone that could help me, 🙂