.\"return the arctangent of a float .DT atan $MUDNAME$ driver help atan .SH Name .SI 5 atan() - return the arctangent of a float .EI .SH Synopsis .SI 5 float atan( float f ); .EI .SH Description .SP 5 5 Returns the arctangent of its argument, `f', measured in radians. .EP .SH See also .SI 5 acos(), asin(), cos(), sin(), tan() .EI