Please can you give me some regular expression help

Hi,

I'm trying to extract a number from a string. The string is of the form H970D80Dia4W19L19WT856 and I want to extract the number after the 'D', in this case 80. But regular expressions are confusing me, I can get this far

regexp(file.name,'[D]\d+','match')

Which gives 'D80', but I can't get rid of the 'D'. Can you help me with this? The strings may be different lengths and can have a different number of characters to the left and right of what I want to extract.

Also is there a good cheat sheet I can print for future reference?

Answer 1

[Andrei Bobrov]

regexp('H970D80Dia4W19L19WT856','(?<=D)\d+','match')

[jlt199]

Thank you very much for your quick response

[Thorsten]

(?<=D) is a "positive look behind assertion" which is itself not part of the match: The match is only valid if there is a "D" in front of it. Nice solution.

Answer 2

[Thorsten]

c = regexp(file.name, 'D(\d+)', 'tokens')

[jlt199]

Thanks for your response too, both answers are very helpful