In reply to Rick Wicklin.

Hey Rick, when using codes in your example to generate numbers from a Normal(or any other distributions) with predefined mean, std, maximum and minimum, I failed to get the "T" with specified moments. My mean=599, std=640 max=7320 min=39. Is there any other options available to handle this? Find a discussion here:http://confounding.net/2010/12/01/randomly-generating-a-truncated-normal-distribution/; As trying it with the parameters above, still suffer big variations in the moments.Thanks in advance for your comments.