Bash number
2016年1月15日 — In bash, you should do your check in arithmetic context: if (( a > b )); then ... fi. For POSIX shells that don't support (()) , you can use -lt and -gt . ,Arithmetic in POSIX shells is done with $ and double parentheses (( )) : echo "$(($num1+$num2))". You can assign from that (sans echo ):
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 Bash number 相關參考資料
bash how to add numbers - Mastering UNIX Shell
Bash provides a lot of methods how to add numbers. First of all is use $(( )) echo $((2+2+1)). Output: 5. If we ... http://www.masteringunixshell. Comparing numbers in Bash - Stack Overflow
2016年1月15日 — In bash, you should do your check in arithmetic context: if (( a > b )); then ... fi. For POSIX shells that don't support (()) , you can use -lt and -gt . https://stackoverflow.com how can I add (subtract, etc.) two numbers with bash? - Unix ...
Arithmetic in POSIX shells is done with $ and double parentheses (( )) : echo "$(($num1+$num2))". You can assign from that (sans echo ): https://unix.stackexchange.com How can I add numbers in a Bash script? - Stack Overflow
2011年6月15日 — For integers: Use arithmetic expansion: $((EXPR)) num=$((num1 + num2)) num=$(($num1 + $num2)) # Also works num=$((num1 + 2 + 3)) ... https://stackoverflow.com How do I test if a variable is a number in Bash? - Stack Overflow
One approach is to use a regular expression, like so: re='^[0-9]+$' if ! [[ $yournumber =~ $re ]] ; then echo "error: Not a number" >&2; exit 1 fi. If the value is not ..... https://stackoverflow.com How to increment a variable in bash? - Ask Ubuntu
2013年12月3日 — The variable is a number, though bash appears to be reading it as a string. Bash version 4.2.45(1)-release (x86_64-pc-linux-gnu) on Ubuntu ... https://askubuntu.com Math Arithmetic: How To Do Calculation in Bash? - Shell-Tips!
2020年9月26日 — Before we get into the details on how to do Math in Bash, remember that an integer is a whole number that is not a fraction and is anywhere ... https://www.shell-tips.com Numerical Constants
#!/bin/bash # numbers.sh: Representation of numbers in different bases. # Decimal: the default let "dec = 32" echo "decimal number = $dec" # 32 # Nothing out ... https://tldp.org |