#!/bin/bash
# Takes hourly precip record and creates daily depth, duration, peak fraction and peak intensity records for days with rain.

# get line a place line values in variable array
lineval=`dm x7 x6 x5 x9*0.254 x11*0.254 x13*0.254 x15*0.254 x17*0.254 x19*0.254 x21*0.254 x23*0.254 x25*0.254 x27*0.254 x29*0.254 x31*0.254 x33*0.254 x35*0.254 x37*0.254 x39*0.254 x41*0.254 x43*0.254 x45*0.254 x47*0.254 x49*0.254 x51*0.254 x53*0.254 x55*0.254 x57*0.254 < $1`

# set up hourly value array
np=0
for singval in ${lineval[@]}
do
    let np=np+1
    if [ $np -gt 3 ]
    then
      if [ $np -lt 28 ]
      then
        let index=np-3
        hourvals[index]=$singval
        # echo "hourvals($index) = ${hourvals[index]}"
      fi
    else
        # retain the date values for output section
        dateval[np]=$singval
    fi
    if [ $np -eq 28 ]
    then
      # reset extraction counter
      np=0
      if [ "$singval" != "0" ]
      then
        echo "${hourvals[@]}"
        # create statistics for line
        index=0
        begrain=0
        endrain=0
        cntrain=0
        maxrain=0
        locmaxrain=0
        for hourval in ${hourvals[@]}
        do
            let index=index+1
            # find first rain hour
            if [ "$begrain" -eq "0" ]
            then
                if [ "$hourval" != "0" ]
                then
                    begrain=$index
                fi
            fi
            # find last rain hour
            if [ "$hourval" != "0" ]
            then
                endrain=$index
            fi
            let durrain=endrain-begrain+1
            # count number of rain hours
            if [ "$hourval" != "0" ]
            then
                let cntrain=cntrain+1
            fi
            # check for tie on values 
            if [ "$hourval" = "$maxrain" ]
            then
                let cntmaxtie=cntmaxtie+1
                locmaxrain=`echo "$locmaxrain $index $cntmaxtie" | dm "x1+((x2-x1)/x3)"`
            fi
            # find location of maximum
            testmax=`echo "$hourval $maxrain" | dm "if x1 > x2 then x1 else 0"`
            if [ "$testmax" != "0" ]
            then
                cntmaxtie=1
                locmaxrain=$index
                maxrain=$testmax
            fi
        done
        # calculate the output values
        durrain=`echo "$endrain $begrain $cntrain" | dm "if (x1-x2+1)/x3 > 2 then x3*2 else x1-x2+1"`
        timepeak=`echo "$endrain $begrain $locmaxrain" | dm "(x3-x2+0.5)/(x1-x2+1)"`
        intensepeak=`echo "$maxrain" | dm "x1*2"`
        echo " ${dateval[1]} ${dateval[2]} ${dateval[3]} $singval $durrain $timepeak $intensepeak"
      fi
    fi
done