Regex search in text files using Windows Grep

Question

this is driving me crazy. How do I write a regular expression to determine higher value than 0.5 in a search string please?

For example: sd=0.398 sd= is the mandatory text in text document I am searching for using Windows Grep and this string is always 4 digits long after decimal point.

and I would like to search for entries higher than 0.5

Those can be: 0.501 1.567 12.567

Answer 1

以下正则表达式应与sd=匹配，后跟一个十进制数字，该数字在小数点后正好是三位（其中，小数点后的第一位是5+）。

sd=[0-9]+\\.[5-9][0-9][0-9]

Answer 2

I try this.

sd=[0-9]+\.[5-9][0-9]*

SEE DEMO: http://regex101.com/r/dF8nC3/1