Thread: distance and azimuth

Started: 2011-01-13 05:24:52
Last activity: 2011-01-13 05:24:52
Topics: SAC Help
Sierra Boyd
2011-01-13 05:24:52
Hello,

I would like to know how to get the distance and azimuth of a station
with respect to the hypocentral info, evla and evlo.

I read in a sac file that came from IRIS. I then change the values of
evla and evlo. I then listhdr inclusive to look at all the header
values. The distance and azimuth are not updated.

However I can get the distance and azimuth of a station with respect
to an event when I download miniSEED data from another source and
convert it to SAC format. I then change the values of evla and evlo as
above and the distance and azimuth are listed.

Any clarification as to why my first attempt does not reveal an
updated distance and azimuth would be greatly appreciated.

Best regards,
--sierra

15:05:42 v.01697673