比较bash中的负数 [英] Compare negative numbers in bash

问题描述

我如何完成涉及负数的数字比较？

  if [[-2> -1]];那么
 echo-2> -1
 else 
 echo-2 <=  -  1
 fi 
  / pre> 
 
 
我也尝试了
  -1'];那么
  
，但条件总是表现为-2大于-1。
 
 
 
当我不使用负数时，比较工作。
 
 
 
我想在纯bash中使用解决方案。 p> 
 
解决方案
似乎可以正常运作：
  if [[-2-gt-1]];那么
 echo-2> -1
 else 
 echo-2 <=  -  1
 fi 
  / pre> 
 
 
输出：
  -2< =  -  1 
  
您可能想使用（（...）），其使得能够根据Shell算术的规则来评估表达式。
  $（（-2 < -1））& echo小于或等于|| echo Larger 
小于或等于
 $（（-2 <= -3））&& echo小于或等于|| echo Larger 
 Larger 
  
 
How can i accomplish number comparison involving negative numbers?
if [[ "-2" > "-1" ]]; then
    echo "-2 >-1"
else
    echo "-2 <=-1"
fi
I also tried 
if [ '-2' -lt '-1' ]; then
but the condition always behaves as if -2 would be greater than -1.

The comparisons work when i do not use negative numbers.

I would like a solution in pure bash if possible.
解决方案
Seems to work correctly:
if [[ "-2" -gt "-1" ]]; then
    echo "-2 >-1"
else
    echo "-2 <=-1"
fi
Output:
-2 <=-1
You might want to use ((...)) which enables the expression to be evaluated according to rules of Shell Arithmetic.
$ ((-2 <= -1)) && echo Smaller or equal || echo Larger
Smaller or equal
$ ((-2 <= -3)) && echo Smaller or equal || echo Larger
Larger


                        
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