added NaN test for Phi
added NaN test for Phi_approx
added NaN test for acos
added NaN test for acosh
added NaN test for asinh
added NaN test for asin
added NaN test for atan and atanh
added NaN test for cbrt
added NaN test for cos
added NaN test for cosh
added NaN test for digamma
added NaN test for exp
added NaN test for exp2
added NaN test for expm1
added NaN tests for fabs
added NaN test for gamma_p
added NaN test for gamma_q
added NaN test for hypot
added NaN test for atan2
added NaN test for inv