Thread: Need help

Started: 2017-02-20 20:11:59
Last activity: 2017-02-20 20:11:59
Topics: SAC Help
Sachin Tiwari
2017-02-20 20:11:59
Hello Everyone,

I am a new sac user and want to do an arithmetic operation on sac header.

My user0 headers contains ray parameter values in sec/rad and want it to
convert to sec/km and store it in user4.

Please help me in this regard.

Thank you very much.
*Sachin Kumar *
*Junior Research Fellow (JRF)*
*Dept. of Applied Geophysics*
*Indian School Of Mines, Dhanbad*
*Jharkhand- 826004, India.*
*Mobile No.:+91-7631056163, +91-8540016927*
*Email : **sachinism15<at>gmail.com <sachinism15<at>gmail.com>*

  • Geo .
    2017-02-20 17:47:20
    Hi Sachin,
    Here're some guidelines. Please refer SAC Primer Book in case you want more
    details.

    First read in USER0 to sac blackboard.
    SETBB rayr &1,USER0&

    Then declare your conversion factor, say x
    SETBB conft x

    and then multiply ray parameter in sac/rad by conversion factor, which
    gives ray parameter in sec/km
    SETBB rayk (MULTIPLY %rayr% %conft%)

    Finally you write this to sac header user4, and write over
    CHNHDR USER4 %rayk%
    WRITE OVER

    Januka.


    Januka Attanayake
    Postdoctoral Research Associate

    Institut für Geophysik
    Westfälische Wilhelms - Universität Münster
    CorrensstraBe 24
    48149 Münster
    Germany

    University email: jattanayake<at>uni-muenster.de
    Homepage: http://sites.google.com/site/janukaattanayake/

    On 20 February 2017 at 07:43, Sachin Tiwari <sachinism15<at>gmail.com> wrote:

    Hello Everyone,

    I am a new sac user and want to do an arithmetic operation on sac header.

    My user0 headers contains ray parameter values in sec/rad and want it to
    convert to sec/km and store it in user4.

    Please help me in this regard.

    Thank you very much.
    *Sachin Kumar *
    *Junior Research Fellow (JRF)*
    *Dept. of Applied Geophysics*
    *Indian School Of Mines, Dhanbad*
    *Jharkhand- 826004, India.*
    *Mobile No.:+91-7631056163 <+91%2076310%2056163>, +91-8540016927
    <+91%2085400%2016927>*
    *Email : **sachinism15<at>gmail.com <sachinism15<at>gmail.com>*


    ----------------------
    SAC Help (http://ds.iris.edu/message-center/topic/sac-help/)

    Sent from the IRIS Message Center (http://ds.iris.edu/message-center/)
    Update subscription preferences at http://ds.iris.edu/account/profile/



10:02:25 v.01697673