Regex to integer\float

[magnusbaeck (Magnus Bäck)]

See this response from earlier this morning:

Gsub specific characters but not all of them in value

You'll have to use a ruby filter for that. Something similar to ruby { code => " event.to_hash.each { |k, v| event[k] = v.to_f if k.start_with? 'metric-' } " } should work.