Remove quotes surrounding number

Question

I have a file with the lines looking similar to:

"somestring": "20.000",

I want to remove the quotes around 20.000.

Other use cases are

"somestring": "20",
"somestring": "blahhhah 3",
"somestring": "",

which should give

"somestring": 20,
"somestring": "blahhhah 3",
"somestring": "",

Obvious regex to recognize numbers is [0-9]+ and [0-9].[0-9]+ for decimals. I was told this is possible with the sed command as it can backreference, however I do not know how to use the sed command. Can someone please provide me with any linux command to accomplish this?

Answer 1

$ sed -r 's@"([0-9]+(\.[0-9]+)?)",\s*$@\1,@' file
"somestring": 20.000,
"somestring": 20,
"somestring": "blahhhah 3",
"somestring": "",