Need Variable Time Step to Avert Unstable Numerical Integ. Exceeding Limits of Double

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I'm attempting to use a "try-catch" construct to try to compute a value and assign it to a variable, intending to "catch" any result that exceeds the defined magnitude limits of the variable. If I'm using a type "double" for the variable, could someone please provide some insight relative to how to detect a computation that exceeds the limits of a "double"? Thank you.