R/EPOCHday.R

In RSEIS: Seismic Time Series Analysis Tools

EPOCHday<-function(yr, jd=1, origyr=1972)
  {
    ########  return number of days since the origin
    if(missing(origyr)) { origyr=1972 }
    if(missing(jd)) {

      jd =1
    }
   
    myr = min(yr, na.rm=TRUE)
    if(is.null(myr)) { return(list(jday=1, origyr=origyr)) }
    if( myr<origyr ){ origyr  = myr  }

    

    jj =tojul(yr, 1, 1)- tojul(origyr, 1, 1)+ jd
    
    
   #### jj =tojul(yr, moday$mo, moday$dom)- tojul(origyr, 1, 1)+1


    #######   alternative way based on unix time codes
    ########  zz =  as.numeric(ISOdate(yr, moday$mo, moday$dom) - ISOdate(origyr, 1, 1))

    return(list(jday=jj, origyr=origyr))
  }