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Arithmetic on a Float in bash

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Top Forums Shell Programming and Scripting Arithmetic on a Float in bash
# 8  
Old 10-24-2015
Note: the $[ ... ] is a non-standard, bash-specific legacy construct that has been deprecated since bash 2.0 and is now no longer in the man pages, so it should be regarded as an undocumented feature, which could be removed from future versions..

Instead, $(( .. )) should be used, which is also used in any other POSIX compliant shell.
# 9  
Old 10-24-2015
Quote:
Originally Posted by wisecracker
.
.
.
Important note both methods do not work with the number 80 but do if converted to 80.0 float equivalent.
As this little trick doesn't really do arithmetics, it needs the dot to lock in on.
# 10  
Old 10-24-2015
Quote:
Originally Posted by Scrutinizer
Note: the $[ ... ] is a non-standard, bash-specific legacy construct that has been deprecated since bash 2.0 and is now no longer in the man pages, so it should be regarded as an undocumented feature, which could be removed from future versions..

Instead, $(( .. )) should be used, which is also used in any other POSIX compliant shell.
Thanks...

I was/am aware, but the OP is using bash.
Sadly, I use(d) this method in AudioScope.sh from day one so that code is lumbered with this legacy.
However apart from my important note I did like RudiC's approach so I decided to reduce the number of characters, (ignoring spaces).
I will refrain from using this method again but will have to continue using it in the above project to keep the coding style the same...

Once again thanks and I will use the parentheses method in any future help...
# 11  
Old 10-24-2015
Save another char?echo $((${number%?.*}-2))0
This User Gave Thanks to RudiC For This Post:
wisecracker
# 12  
Old 10-24-2015
Quote:
Originally Posted by RudiC
Save another char?echo $((${number%?.*}-2))0
Terrific stuff, that is cool...

I just love your lateral thinking head...

Dare I use square brackets and reduce it by another two characters?
Only joking... ;oD
# 13  
Old 10-24-2015
Quote:
Originally Posted by RudiC
Save another char?echo $((${number%?.*}-2))0
Nice, a tiny nitpick would be that number=28.152 results in 00...
This User Gave Thanks to Scrutinizer For This Post:
RudiC
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