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Is there a fast function isFloatValid(float f) ?

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Hi, Do you know of a fast function which checks whether a float is valid or not? 1.#INF0 would be an invalid value I found the following code:
	unsigned short int axreg;
		fld value		// load float value		

		fxam			// check it

		fstsw ax		// get status word		

		mov axreg,ax	// let us access in c++	

	if ((axreg&0x500)!=0x500)	// check for INF

Is this enough? Or can a flot have another invalid value? I always thought division by zero and overflow have distinct values. Thanks

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I think an invalid float in the FPU was called a Nan.. it''s been awhile. check the processor manuals at

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