bash_scripting
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Bash Scripting
- Maths
- colours
- highlighting - Page not found.
bc
You can use bc in bash to do maths calculations with decimals. The man pages can be found:
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http://unixhelp.ed.ac.uk/CGI/man-cgi?bc+1 |
Example Calulation
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bc -l <<< "20 / ( 20 + 80) * 100 " |
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20.00000000000000000000 |
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-l = --mathlib = Defines the standard math library |
Limiting the decimal place
You can then use this with printf to limit the number of decimals shown: \\The example below shows the results to 3 decimal places. You can replace the 3 with what ever value you wish to place
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printf "%.3f\n" $(bc -l <<< "20 / ( 20 + 80) * 100 ") |
You can also use bc with variables:
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bc -l <<< "($used / ( $free + $used) ) * 100 ") |
Comparing Decimals with bc
You are able to compare decimal numbers using bc. The output will return 1 or 0 depending on the results. You can then use this with an if statment -le / -ge etc
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1.4 '<' 1.3 | bc -l |
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example= $(echo 1.4 '<' 1.3 | bc -l)if [ $example-eq 0 ]; thenelif [ $example-eq 1 ]; thenfi |
bash_scripting.1431206773.txt.gz · Last modified: 2024/05/23 07:26 (external edit)