If you can use awk (I suppose you can), than this there's a script which does what you need:
#!/bin/bash
RESULT_FILE_NAME="datafile.new"
cat datafile.fix | head -4 > datafile.new
cat datafile.fix | tail -n +5 | awk -F"[, ]" '{if(!$2){print()}else{print($2","$1, $3)}}' >> datafile.new
Passing -F"[, ]" allows awk to split columns both by , and space and all that remains is just print columns in a needed format. The downsides are that we should use if statement to preserve empty lines and file header also should be treated separately.
Another option is using sed:
cat datafile.fix | sed -E 's/([a-zA-Z]+),([a-zA-Z]+) ([0-9]+)/\2,\1 \3/g' > datafile.new
The downside is that it requires regex that is not as obvious as awk syntax.
What could be done by sed?
there will be a similar expression as
awk, but usingsed. It's just another test processor and it doesn't make a major differenceJust added a solution using
sed. It works better because it preserves file structureThere is no need for cat and head when using awk as awk can do all this processing for you.