I seem to be having trouble constructing a regex that I'm sure ought to be straightforward.

I want to read lines from a file which contain one or more alphanumeric characters, followed by either 2 or 4 positive real numbers, separated by white space. For example:

Abc 	21223.7   21225.33   22270.3   22280.1
Def	21600.23  24567.43

The only regexp I've managed to come up with which does what I want is:

m/^(\w+)\s+([\d\.]+)\s+([\d\.]+)(?:\s+([\d\.]+)\s+([\d\.]+))?/
[download]

but I feel sure that there must be something shorter and more elegant.

I tried using:

m/^(\w+)(?:\s+([\d\.]+)\s+([\d\.]+)){1,2}/
[download]

Which works when there are two numbers, but puts the last two numbers into $2 and $3, throwing away the first two numbers from lines with four numbers (higher number variables are all empty).

If I remove the ?: the same thing happens but in $3 and $4.

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