How to use a variable in an awk expression
I'm trying to make this command:
sed bla bla filename | awk '{printf "%s %s_entry_%.3f %.3f %.3f %.3f",$1,$3,$4,$5,$6,$7}'
But the thing is开发者_StackOverflow中文版, i want the %.3f part to be variable. So in one case it could be %.3f and in another it could be %.3f %.3f %.3f. So i'll just use a static one in my example code for clarity. So if i want 4 of these %.3f and put them in variable $values like so:
values="%.3f %.3f %.3f %.3f"
Then how can I put this string in the awk expression, without making awk to just put literally "${values}" in there. The following is my non-working-attempt:
sed bla bla filename | awk '{printf "%s %s_entry_${values}",$1,$3,$4,$5,$6,$7}'
you can use -v
option of awk to pass in variable from the shell
#!/bin/bash
awk -v values="${values}" '{gsub("blah","replace");printf "%s %s_entry_"values ....}' file
the gsub()
function is to replace what you have with that sed
command. So just one awk command will do. sed
is redundant in this case (and most other cases where awk is used)
Easiest to use actual awk variables:
sed bla bla filename | awk -v values="$values" '{printf "%s %s_entry_"values,$1,$3,$4,$5,$6,$7}'
Or with bash:
awk -v values="$values" '{printf "%s %s_entry_"values,$1,$3,$4,$5,$6,$7}' <(sed bla bla filename)
If you mean that values
is a shell variable, then this will work:
sed bla bla filename | awk '{printf "%s %s_entry_"ENVIRON["values"],$1,$3,$4,$5,$6,$7}'
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