Multiple columns replace with null values.

I am trying to replace the partcular columns(Col3,col5,col20,col44,col55,co56,col59,col60,col61,col62,col74,col75,col88,col90,col91,col93,col94,col95) with empty

Input file

Col1,col2,col3,col4,col5------,col100
1,2,3,4,5,---------,100
3,4,5,6,7,---------,300

Output :
Col1,col2,col3,col4,col5------col100
1,2,,4,,---------100
3,4,,6,,---------300

Tried with sed but not working.
sed command not helping because I am replacing the entire column with null value.

"The scenario simply replace few columns with null values in a file."

Any advices on sed command to replace the entire column as null.

If you have GNU awk and assuming your input is just a simple csv (i.e. no ',' characters within a field), try something like:

$ awk '{$3=$5=""}1' FS=, OFS=, file.csv
Col1,col2,,col4,,col100
1,2,,4,,---------,100
3,4,,6,,---------,300

(the above does only columns 3 & 5 - you'd need to add the others)

Its resolved.

I found another link the solution.
I am unable to find the resolved button.

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