Constructing numbers from input lines

Shell Programming and Scripting
1

I have a file with the information shown and I want to capture the
entry having the rgdt tag and taking the value (the location of the represents the decimal point, for example 0p50 represents 0.50)

I then want to divide the number at the end of each line by the value 0.50

I want to do this using awk

npt02-z30-sr65-rgdt0p50-dc0p006-16x12drw.csmis  345
npt02-z30-sr65-rgdt0p50-dc0p006-16x12drw.csmis 45
npt02-z30-sr65-rgdt0p50-dc0p006-16x12drw.csmis 456
npt02-z30-sr65-rgdt0p50-dc0p006-16x12drw.csmis 4523
npt02-z30-sr65-rgdt0p50-dc0p006-16x12drw.csmis 2342
npt02-z30-sr65-rgdt0p50-dc0p006-16x12drw.csmis 33425 
npt02-z30-sr65-rgdt0p50-dc0p006-16x12drw.csmis 3512
2

Like this?

awk -F'[- \t]*' 'sub(/rgdt/,x,$4){sub(/p/,".",$4);print $7/$4}' infile
3

the rgdt0p50 can occur in any position not necessarily $4

4

Except the last column? only once per line?

5

That's correct

Actual file might actually be like this. Want to strip away the first entry but remember the value in the line 0.50 where I need to divide the last number with 0.50

npt02-z30-sr65-rgdt0p50-dc0p006-16x12drw-run1.log:0. Rms Value    = 0.00551131
npt02-z30-sr65-rgdt0p50-dc0p006-16x12drw-run1.log:1. Rms Value    = 0.0105689
npt02-z30-sr65-rgdt0p50-dc0p006-16x12drw-run1.log:2. Rms Value    = 0.0137097
npt02-z30-sr65-rgdt0p50-dc0p006-16x12drw-run1.log:3. Rms Value    = 0.0163874
npt02-z30-sr65-rgdt0p50-dc0p006-16x12drw-run1.log:4. Rms Value    = 0.0187422
npt02-z30-sr65-rgdt0p50-dc0p006-16x12drw-run1.log:5. Rms Value    = 0.0197708
npt02-z30-sr65-rgdt0p50-dc0p006-16x12drw-run1.log:6. Rms Value    = 0.0208463
npt02-z30-sr65-rgdt0p50-dc0p006-16x12drw-run1.log:7. Rms Value    = 0.0217194
npt02-z30-sr65-rgdt0p50-dc0p006-16x12drw-run1.log:8. Rms Value    = 0.0226114
npt02-z30-sr65-rgdt0p50-dc0p006-16x12drw-run1.log:9. Rms Value    = 0.0229611
npt02-z30-sr65-rgdt0p50-dc0p006-16x12drw-run1.log:10. Rms Value    = 0.0239331
npt02-z30-sr65-rgdt0p50-dc0p006-16x12drw-run1.log:11. Rms Value    = 0.025327
npt02-z30-sr65-rgdt0p50-dc0p006-16x12drw-run1.log:12. Rms Value    = 0.0250741
npt02-z30-sr65-rgdt0p50-dc0p006-16x12drw-run1.log:13. Rms Value    = 0.0255705
npt02-z30-sr65-rgdt0p50-dc0p006-16x12drw-run1.log:14. Rms Value    = 0.0266015
npt02-z30-sr65-rgdt0p50-dc0p006-16x12drw-run1.log:15. Rms Value    = 0.0268534
npt02-z30-sr65-rgdt0p50-dc0p006-16x12drw-run1.log:16. Rms Value    = 0.0264882
npt02-z30-sr65-rgdt0p50-dc0p006-16x12drw-run1.log:17. Rms Value    = 0.0269775

Actually it would be good to store the value 0.50 and store it so I can determine 1/(0.5*0.5), then multiply
the last number by this value.

I should end up with

0. Rms Value    = 0.00551131/(0.50*0.50)
1. Rms Value    = 0.0105689/(0.50*0.50)
2. Rms Value    = 0.0137097/(0.50*0.50)
3. Rms Value    = 0.0163874/(0.50*0.50)
4. Rms Value    = 0.0187422/(0.50*0.50)
5. Rms Value    = 0.0197708/(0.50*0.50)
6. Rms Value    = 0.0208463/(0.50*0.50)
7. Rms Value    = 0.0217194/(0.50*0.50)
8. Rms Value    = 0.0226114/(0.50*0.50)
9. Rms Value    = 0.0229611/(0.50*0.50)
10. Rms Value    = 0.0239331/(0.50*0.50)
11. Rms Value    = 0.025327/(0.50*0.50)
12. Rms Value    = 0.0250741/(0.50*0.50)
13. Rms Value    = 0.0255705/(0.50*0.50)
14. Rms Value    = 0.0266015/(0.50*0.50)
15. Rms Value    = 0.0268534/(0.50*0.50)
16. Rms Value    = 0.0264882/(0.50*0.50)
17. Rms Value    = 0.0269775/(0.50*0.50)
6 
awk 'sub(/.*rgdt/,x){sub(/p/,".");sub(/-.*/,x,$1);print $NF/$1}' infile
7

At the moment I've got the following code, and need to do this additional thing, divide last number with square of the rgdt value.

          grep "Rms Value" $f.log                          \
            | awk  '{   sub(/[^:]*:[0-9]*\.[ \t]*/,x);     \
                        print $1" "$2" "$3" "$4" "$NF   \
                    }' > $f.csmis
8

Using ksh, bash, ... If using ksh93, then you can use shell builtin floating calculation. In ksh93 case no need to use external bc.

#!/usr/bin/ksh93

#typeset -F2 value1 value2  result # float in ksh93

grep "Rms Value" logfile | while read line
do
        line=${line//-/ }  # convert - => space
        desim="1"  # default
        for fld in $line
        do
                case "$fld" in
                rgdt*) desim=${fld/rgdt/}   # rm rgdt
                       desim=${desim/p/.}   # p=>.
                       ;;
                esac
        done
        value1=$fld     # lastvalue
        value2=$desim
        #((result=value1/value2))
        result=$(echo "$value1 / $value2 " | bc )
        echo "$value1 / $value2 = $result"
done