Pysacio

PYSACIO - SAC IO library for Python

Python module to read and write binary SAC (Seismic Analysis Code) files.

NOTE: This module is outdated. Please use the module pyrocko.io.sac from the Pyrocko library (https://pyrocko.org/).

Usage is like this:

import pysacio

Read a SAC file:

sac = pysacio.SacFile('test.sac')

Access header values (assignment is also fine):

sac.delta 0.5

Access the data: it is returned as a NumPy array:

sac.data[0] array([ 0., 0., 1., 2., 0.], dtype=float32)

The data is in data[0] because in some sac files, e.g. with spectra stored, there are more than one data parts.

To simplify dealing with the reference time of the SAC file, I implemented this:

sac.get_ref_time() Traceback (most recent call last): File "<stdin>", line 1, in ? File "/bonus/lib/python2.4/site-packages/pysacio.py", line 64, in get_ref_time raise SacError('Not all header values for reference time are set.') pysacio.SacError: Not all header values for reference time are set.

... aaah, OK, the time headers were not set in this file, so let's set them to the current system time, for the demo:

import time sac.set_ref_time(time.time()) sac.get_ref_time() 1250703611.993 sac.nzyear 2009 sac.nzjday 231 sac.nzhour 17

You can 'print' the SAC object:

print sac delta: 0.5 b: 0.0 e: 2.0 nzyear: 2009 nzjday: 231 nzhour: 17 nzmin: 40 nzsec: 11 nzmsec: 993 nvhdr: 6 npts: 5 iftype: 1 leven: 1 lpspol: 0 lovrok: 1 lcalda: 1 unused17: 0 kevnm: -12345 -12345

And to write it to file:

sac.write('newfile.sac')