By searching Google with a rudimentary search query:
http://www.google.com/search?source=...sp+-+isnumeric
hint: the answer to your question is actally part of your question, though not 100% exact.
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Read this if you want to know how to get a correct reply for your question:
http://www.catb.org/~esr/faqs/smart-questions.html
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.: Wrox Technical Editor / Author :.
Wrox Books 24 x 7
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