isNaN()

isNaN(x) provides a reliable way to determine if x is one of the "not a number" floating point forms.

isNaN(x) provides a reliable way to determine if x is one of the "not a number" floating point forms.

Comparing x==NaN does not work because any relational operation involving NaN always return false, even (NaN==NaN)! This routine is specialized for all SimTK scalar types:

• float, double
• std::complex<P> (P is one of the above precisions)
• SimTK::conjugate<P>
• SimTK::negator<T> (T is any of the above)

For complex and conjugate types, isNaN() returns true if either the real or imaginary part or both are NaN.