484 Appendix B The Standard C Librarydouble atan (x)
Returns the arctangent of xas an angle expressed in radians in the range [–π/2,π/2].
double atanh (x)
Returns the hyperbolic arctangent of x,|x|≤ 1.
double atan2 (y, x)
Returns the arctangent of y/xas an angle expressed in radians in the range [–π,π].
double ceil (x)
Returns the smallest integer value greater than or equal to x. Note that the value is
returned as a double.
double copysign (x, y)
Returns a value whose magnitude is that of xand whose sign is that of y.
double cos (r)
Returns the cosine of r.
double cosh (x)
Returns the hyperbolic cosine of x.
double erf (x)
Computes and returns the error function of x.
double erfc (x)
Computes and returns the complementary error function of x.
double exp (x)
Returnsex.
double expm1 (x)
Returnsex– 1.
double fabs (x)
Returns the absolute value of x.
double fdim (x, y)
Returns x– yif x > y; otherwise, it returns 0.
double floor (x)
Returns the largest integer value less than or equal to x. Note that the value is
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