UNIX for Beginners Questions & Answers

Ubuntum, Bash version: 4.3.46 Bash

INPUT file (csv):
TS133_29BC,xx2274305
TS133_29BC,rps4576240
av137_37BC,wfs2274305
av137_37BC,ftrs4576240
T1S138_30BC,rfss2255526
T1S138_30BC,rgas2274305

OUTPUT files (csv):
File TS133_29BC
TS133_29BC,xx2274305
TS133_29BC,rps4576240

File av137_37BC
av137_37BC,wfs2274305
av137_37BC,ftrs4576240

File T1S138_30BC
T1S138_30BC,rfss2255526
T1S138_30BC,rgas2274305

for ((b=$1; b<=96; b++))

    do

dddd=*"_"${b}"BC"

grep -w "$dddd" > $dddd

    done

find . -size 0 -delete

for((b=$1 ...

for ((b=1; b<=96; b++))      do  dddd=*"_"${b}"BC"  grep -w "$dddd" inputfile > $dddd      done

$ man regex

REG_BADRPT
              Invalid use of repetition operators such as using '*' as the first character.

. Matches any single character
? The preceding item is optional and will be matched, at most, once
* The preceding item will be matched zero or more times.

dddd=....."_"${b}"BC"

echo {01..96}

for b in {01..96}
do
  ...
done

while IFS=, read left right
do
  if [[ $left == *[0-9][0-9]BC ]]
  then
    if [[ $left != $prev ]]
    then
      exec 3> "$left".csv
      prev=$left
    fi
    echo "$left,$right" >&3
  fi
done < inputfile.csv