Trying to add text at the end of multiple lines in a txt file-CodePudding

I have a project in Bash and I need a way of calculating averages of students and adding those averages in a text file. The text file is the following:

:NOM Prenom:CODE                :.Tp1 :.Intra:.Tp2 :.Tp3 :.Final :.TP4 :.Moy:.Lettre:
actarusx:Actarus  :ACTA28658105 : 45.5: 75.00:100.0: 95.0:  48.50: 90.0:  
alcorxxx:Alcor    :ALCO18083408 : 83.0: 64.75: 95.0: 87.5:  74.00: 97.0:  
venusiax:Venusia  :VENU13097708 : 83.0: 55.00: 95.0: 87.5:  41.50: 97.0:  
phenicia:Phenicia :PHEN14100790 : 94.0: 50.50: 95.0: 95.0:  59.50: 99.0:  
mizarxxx:Mizar    :MIZA22128106 : 98.0: 95.50: 95.0:100.0:  80.50: 90.0:  
procyonx:Procyon  :PROC01033701 : 99.0: 99.50:100.0: 95.0:  98.00:100.0:  
flamxxxx:Flam     :FLAM26077904 : 89.0: 37.25: 97.5: 87.5:  63.50: 97.0:  
johannxx:johann   :JOHA23058000 : 94.0: 99.25:100.0: 95.0:  36.00:100.0:  
wrightxx:Wright   :WRIG21058103 : 99.0: 100.0:100.0:100.0:  100.0: 97.0:  
cragxxxx:Grag     :CRAG05018002 : 99.0: 90.00: 90.0:100.0:  97.00: 99.0:  
malaxxxx:Mala     :MALA09557914 : 96.0: 69.50:100.0:100.0:  34.00: 47.0:

I want to calculate the total average of TP1,2,3,4, Intra and Final. Once I have the average for each student (one student per line), I want to add the average under the column called Moy:. Note: For some reason, the categories all got moved around so the first line of floats is associated with tp1 and so forth.

At the moment I have:

nbline=0
while read line; do
   if[ $nbline -eq 0 ]; then #To skip the first line with each categories
      let nbline =1
   else
     # Code that allows me to get the grades for each categories (already provided by the teacher)
     # eg. for the first student the code will do tp1=45.5, intra=75, etc...
     # Code that allows me to calculate the average (already provided by the teacher)
     # moy is the average found

Once I find moy, I'm not sure how to add it in the column Moy: of each student. This is my first time coding in unix/linux and my teacher didn't spend a lot of time (if any at all) teaching us the different commands so help would be greatly appreciated.

Thank you very much

CodePudding user response：

Would you please try the following:

#!/bin/bash

while read -r line; do
    if (( nr   == 0 )); then                    # header line
        echo "$line"
    else
        mapfile -d: -t a <<< "$line"            # assign array "a" to the columns
        ave=$(echo "scale=2; ( $(IFS= ; echo "${a[*]:3:6}") ) / 6" | bc)
        printf "%s%6s\n" "$line" "$ave"
    fi
done < file.txt

Output:

:NOM Prenom:CODE                :.Tp1 :.Intra:.Tp2 :.Tp3 :.Final :.TP4:.Moy:.Lettre:
actarusx:Actarus  :ACTA28658105 : 45.5: 75.00:100.0: 95.0:  48.50: 90.0: 75.66
alcorxxx:Alcor    :ALCO18083408 : 83.0: 64.75: 95.0: 87.5:  74.00: 97.0: 83.54
venusiax:Venusia  :VENU13097708 : 83.0: 55.00: 95.0: 87.5:  41.50: 97.0: 76.50
phenicia:Phenicia :PHEN14100790 : 94.0: 50.50: 95.0: 95.0:  59.50: 99.0: 82.16
mizarxxx:Mizar    :MIZA22128106 : 98.0: 95.50: 95.0:100.0:  80.50: 90.0: 93.16
procyonx:Procyon  :PROC01033701 : 99.0: 99.50:100.0: 95.0:  98.00:100.0: 98.58
flamxxxx:Flam     :FLAM26077904 : 89.0: 37.25: 97.5: 87.5:  63.50: 97.0: 78.62
johannxx:johann   :JOHA23058000 : 94.0: 99.25:100.0: 95.0:  36.00:100.0: 87.37
wrightxx:Wright   :WRIG21058103 : 99.0: 100.0:100.0:100.0:  100.0: 97.0: 99.33
cragxxxx:Grag     :CRAG05018002 : 99.0: 90.00: 90.0:100.0:  97.00: 99.0: 95.83
malaxxxx:Mala     :MALA09557914 : 96.0: 69.50:100.0:100.0:  34.00: 47.0: 74.41

mapfile -d: -t a <<< "$line" splits the input line on colons and assign array a to the columns.
$(IFS= ; echo "${a[*]:3:6}") outputs the columns from the 4th to the 9th delimited by sign so the bc command can caluculate the sum of the columns.
If you want to tweak the number of decimal digits of the average, modify the value to -scale=2 and the width %6s in printf format.

CodePudding user response：

LC_ALL="C"

start_col=4
end_col=9
output_col=10
delimiter=":"

awk \
        -F"$delimiter" \
        -v "start=$start_col" \
        -v "end=$end_col" \
        -v "output=$output_col" '
        BEGIN {OFS = FS}
        NR == 1 { print }
        NR !=1 {
          sum=0
          for (i=start; i<=end; i  ) sum=sum $i
          $(output)=" "sprintf("%.2f", sum/((end 1)-start))
          print
}' file.txt

Output:

:NOM Prenom:CODE                :.Tp1 :.Intra:.Tp2 :.Tp3 :.Final :.TP4 :.Moy:.Lettre:
actarusx:Actarus  :ACTA28658105 : 45.5: 75.00:100.0: 95.0:  48.50: 90.0: 75.67
alcorxxx:Alcor    :ALCO18083408 : 83.0: 64.75: 95.0: 87.5:  74.00: 97.0: 83.54
venusiax:Venusia  :VENU13097708 : 83.0: 55.00: 95.0: 87.5:  41.50: 97.0: 76.50
phenicia:Phenicia :PHEN14100790 : 94.0: 50.50: 95.0: 95.0:  59.50: 99.0: 82.17
mizarxxx:Mizar    :MIZA22128106 : 98.0: 95.50: 95.0:100.0:  80.50: 90.0: 93.17
procyonx:Procyon  :PROC01033701 : 99.0: 99.50:100.0: 95.0:  98.00:100.0: 98.58
flamxxxx:Flam     :FLAM26077904 : 89.0: 37.25: 97.5: 87.5:  63.50: 97.0: 78.62
johannxx:johann   :JOHA23058000 : 94.0: 99.25:100.0: 95.0:  36.00:100.0: 87.38
wrightxx:Wright   :WRIG21058103 : 99.0: 100.0:100.0:100.0:  100.0: 97.0: 99.33
cragxxxx:Grag     :CRAG05018002 : 99.0: 90.00: 90.0:100.0:  97.00: 99.0: 95.83
malaxxxx:Mala     :MALA09557914 : 96.0: 69.50:100.0:100.0:  34.00: 47.0: 74.42