if [[ 6 > 50 ]]; then
echo "true"
fi
$ bash script.sh
I'm missing something very obvious here. Why is 6 greater than 50 ??
** EDIT **
I'm also try to solve for
if [[ 6.5 > 50 ]]; then
echo "true"
fi
3 Answers
If you need to compare floats, the easiest way is to call out to an external tool like awk or bc
a=6.1
b=50
if [[ "$(echo "$a > $b" | bc)" -eq 1 ]]; then echo "a greater than b"; fi
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I'm not as familiar with bash scripting (obviously) so I appreciate you answering my "silly" question with a formative and informational answer rather than exercising contempt on me for knowing less than you in this given situation. Cheers @glennJackmanJacksonkr– Jacksonkr2020-09-09 14:03:38 +00:00Commented Sep 9, 2020 at 14:03
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1No worries. There are no silly questions, providing you follow a few sensible guidelines.glenn jackman– glenn jackman2020-09-09 15:42:00 +00:00Commented Sep 9, 2020 at 15:42
If you're comparing integers then use
if [[ 6 -gt 50 ]]; then echo "true"; fi
otherwise since bash cannot handle floating point
if (( $(echo "6.5 > 50" | bc -l) )); then echo "true"; fi
You supplied [[ args ]] which is a conditional expression, when you meant to perform arithmetic evaluation which uses the (( condition )) syntax.
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In certain situations I have a float in there and when I've tried this I get
syntax error: invalid arithmetic operator (error token is ".00 > 50 ")Jacksonkr– Jacksonkr2020-09-09 01:21:05 +00:00Commented Sep 9, 2020 at 1:21 -
1@Jacksonkr Bash does not do floats. A good starting point for questions like these is to consult
man bash.John1024– John10242020-09-09 01:21:58 +00:00Commented Sep 9, 2020 at 1:21 -
man bash: "When used with [[, the < and > operators sort lexicographically using the current locale."