foo bar 12,300.50
foo bar 2,300.50
abc xyz 1,22,300.50
How do I replace all , from 3rd field using awk and pass output to bc -l in the following format to get sum of all numbers:
12300.50+2300.50+1,22,300.50
You can use gsub() funcion as follows. The syntax is:
gsub("find", "replace")
gsub("find-regex", "replace")
gsub("find-regex", "replace", t)
gsub(r, s [, t])
From the awk man page:
For each substring matching the regular expression r in the string t, substitute the string s, and return the number of substitutions. If t is not supplied, use $0. An & in the replacement text is replaced with the text that was actually matched. Use \& to get a literal &.
You can also use the following syntax:
gensub(r, s, h [, t])
From the awk man page:
Search the target string t for matches of the regular expression r. If h is a string beginning with g or G, then replace all matches of r with s. Otherwise, h is a number indicating which match of r to replace. If t is not supplied, $0 is used instead. Within the replacement text s, the sequence \n, where n is a digit from 1 to 9, may be used to indicate just the text that matched the n'th parenthesized subexpression. The sequence \0 represents the entire matched text, as does the character &. Unlike sub() and gsub(), the modified string is returned as the result of the function, and the original target string is not changed.
Example
Create a data file cat /tmp/data.txt
foo bar 12,300.50 foo bar 2,300.50 abc xyz 1,22,300.50
Type the following awk command:
awk '{ gsub(",","",$3); print $3 }' /tmp/data.txt
Sample outputs:
12300.50 2300.50 122300.50
You can pass the output to any command or calculate sum of the fields:
awk 'BEGIN{ sum=0} { gsub(",","",$3); sum += $3 } END{ printf "%.2f\n", sum}' /tmp/data.txt
OR build the list and pass to the bc -l:
awk '{ x=gensub(",","","G",$3); printf x "+" } END{ print "0" }' /tmp/data.txt | bc -l
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{ 1 comment… read it below or add one }
Nice tutorial :-)