i only want to extract the node number (250,251..) only if string cpus: is empty after the colon.
That's seems to be exactly the output from Athanasius's code. Or, if it is not, then please explain in which respect Athanasius's code does not produce what you want. And also show the code you're using.

In reply to Re^4: extracting value in a string after checking value after colon ':' by Laurent_R
in thread extracting value in a string after checking value after colon ':' by t-rex

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