Question

German version of Origin [TM] saves .csv files very odd. However I have many of these .csv files and want to convert them with a script.

A,B
Independent variable,comment1 
"0,4","0,067"
"0,0","0,08"
"0,07","0,02"
"0,09","0,00"

should become

A,B
# Independent variable,comment1 
0.4,0.067
0.0,0.08
0.07,0.02
0.09,0.00

The definition of a comment by Origin seems to be

it is the second line

Answer 1

If there is structure to your csv files, and Kevin’s comment above is correct, then you can use ranges by line number:

sed '2s/^/# /; 3,$s/"\([^,]*\),\([^,]*\)"/\1.\2/g' file

Or a slightly shorter way:

sed '2s/^/# /; 3,$s/,/./g;s/"."/,/g;s/"//g' file

Results:

A,B
# Independent variable,comment1 
0.4,0.067
0.0,0.08
0.07,0.02
0.09,0.00