Bash：预期的整数表达式
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Bash: Integer expression expected
提问by rabotalius
I'm trying to perform simple math, to check if a variable is greater or equal to "1.5"
but I'm getting [: 2.41: integer expression expected
我正在尝试执行简单的数学运算，以检查变量是否大于或等于“1.5”，但我得到了 [: 2.41: integer expression expected
Code:
代码：
reSum=$(expr "scale=1;555/230" | bc)
if [ $reSum -ge "1.5" ]; then
...
fi
How can I do floating-point comparisons in shell script?
如何在 shell 脚本中进行浮点比较？
回答by Steven Penny
if echo 555 230 | awk '{exit / >= 1.5 ? 0 : 1}'
then
# ...
fi
回答by lifus
Edit:
编辑：
The shortest solution that works for me:
对我有用的最短解决方案：
reSum=$(expr "scale=1;555/230" | bc)
if (( `echo $reSum'>='1.5 | bc` )); then
# anything
fi
As pointed out by shellter, [ $(expr "$reSum > 1.5" | bc) ]actually does a lexicographic comparison.
So, for example, expr "2.4 > 18 | bc" // =>0.
正如shellter所指出的，[ $(expr "$reSum > 1.5" | bc) ]实际上是进行了字典比较。因此，例如，expr "2.4 > 18 | bc" // =>0。
However, (( `echo $reSum'>='1.5 | bc` ))does floating point comparison rather than strings.
但是，进行(( `echo $reSum'>='1.5 | bc` ))浮点比较而不是字符串。
