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- FPLIB implements the set of routines described in K&R, Second Edition,
- pp 250-251. In the following descriptions, x and y are of type float,
- and n is of type int. All functions (including ceil and floor) return
- a value of type float.
-
- Remember to declare any routine you use, either explicitly or by
- including MATH.H. If you don't, the compiler will assume the function
- returns a value of type int, and will perform an unwanted conversion.
-
- A domain error occurs if an argument is outside the range for which
- the function is defined (e.g. sqrt(-1.0)). In this case, errno is
- set to EDOM and the result is usually 0.0. A range error occurs if
- the result cannot be represented as a float (e.g. exp(100.0)). In
- this case, errno is set to ERANGE and the result is HUGE_VAL. If the
- function succeeds, errno is not zeroed.
-
- In all trigonometric functions, angles are expressed in radians. Pi
- radians equal 180 degrees.
-
- All routines work in all three resolutions :-)
-
- sin(x) sine of x.
- cos(x) cosine of x.
- tan(x) tangent of x.
- asin(x) inverse sine of x in the range -pi/2 to pi/2.
- acos(x) inverse cosine of x in the range 0 to pi.
- atan(x) inverse tangent of x in the range -pi/2 to pi/2.
- atan2(x,y) inverse tangent of x/y in the range -pi to pi. The
- angle is chosen so that x has the sign of the sine and
- y has the sign of the cosine.
- sinh(x) hyperbolic sine of x.
- cosh(x) hyperbolic cosine of x.
- tanh(x) hyperbolic tangent of x.
- exp(x) e to the power of x.
- log(x) logarithm, base e, of x: x > 0.
- log10(x) logarithm, base 10, of x: x > 0.
- pow(x,y) x to the yth power. A domain error occurs if x=0 and
- y<=0, or if x<0 and y is not an integer.
- sqrt(x) square root of x: x>=0.
- ceil(x) smallest whole number not less than x.
- floor(x) largest whole number not greater than x.
- fabs(x) absolute value of x.
- ldexp(x,n) x, times 2 to the nth power.
- frexp(x,pn) splits x into a fraction between 0.5 and 0.999..., which
- is the returned value, and a power of 2, which is stored
- in the int pointed to by pn. If x is 0, both parts of
- the result are 0.
- modf(x,py) splits x into integral and fractional parts, both with
- the same sign as x. The fraction is returned and the
- integral part is stored in the float pointed to by py.
- fmod(x,y) remainder of x/y, with the same sign as y.
- atof(ps) converts the string ps into a float.
-
- The file MATH.H also defines several mathematical constants.
-