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The math header defines several mathematic functions.
Macros:
HUGE_VAL
Functions:
acos();
asin();
atan();
atan2();
ceil();
cos();
cosh();
exp();
fabs();
floor();
fmod();
frexp();
ldexp();
log();
log10();
modf();
pow();
sin();
sinh();
sqrt();
tan();
tanh();
All math.h functions handle errors similarly.
In the case that the argument passed to the function exceeds the range of that function,
then the variable errno
is set to EDOM
. The value that the function returns is implementation
specific.
In the case that the value being returned is too large to be represented in a double, then
the function returns the macro HUGE_VAL
, and sets the variable errno
to ERANGE
to represent
an overflow. If the value is too small to be represented in a double, then the function returns
zero. In this case whether or not errno
is set to ERANGE
is implementation specific.
errno
, EDOM
, and ERANGE
are defined in the errno.h header.
Note that in all cases when it is stated that there is no range limit, it is implied that the value is limited by the minimum and maximum values of type double.
Declaration:
double acos(double
x);
Returns the arc cosine of x in radians.
Range:
The value x must be within the range of -1 to +1 (inclusive). The returned value is in the range of 0 to pi (inclusive).
Declaration:
Range:double asin(double
x);
Returns the arc sine of x in radians.
The value of x must be within the range of -1 to +1 (inclusive). The returned value is in the range of -p/2 to +p/2 (inclusive).
Range:double atan(double
x);
Returns the arc tangent of x in radians.
The value of x has no range. The returned value is in the range of -p/2 to +p/2 (inclusive).
Range:double atan2(doubly
y, double
x);
Returns the arc tangent in radians of y/x based on the signs of both values to determine the correct quadrant.
Both y and x cannot be zero. The returned value is in the range of -p/2 to +p/2 (inclusive).
Range:double cos(double
x);
Returns the cosine of a radian angle x.
The value of x has no range. The returned value is in the range of -1 to +1 (inclusive).
Range:double cosh(double
x);
Returns the hyperbolic cosine of x.
There is no range limit on the argument or return value.
Range:double sin(double
x);
Returns the sine of a radian angle x.
The value of x has no range. The returned value is in the range of -1 to +1 (inclusive).
Range:double sinh(double
x);
Returns the hyperbolic sine of x.
There is no range limit on the argument or return value.
Range:double tan(double
x);
Returns the tangent of a radian angle x.
There is no range limit on the argument or return value.
Range:double tanh(double
x);
Returns the hyperbolic tangent of x.
The value of x has no range. The returned value is in the range of -1 to +1 (inclusive).
Range:double exp(double
x);
Returns the value of e raised to the xth power.
There is no range limit on the argument or return value.
Range:double frexp(double
x, int *
exponent);
The floating-point number x is broken up into a mantissa and exponent.
The returned value is the mantissa and the integer pointed to by exponent is the exponent. The resultant value is x=mantissa * 2^exponent.
The mantissa is in the range of .5 (inclusive) to 1 (exclusive).
Range:double ldexp(double
x, int
exponent);
Returns x multiplied by 2 raised to the power of exponent.
x*2^exponent
There is no range limit on the argument or return value.
Range:double log(double
x);
Returns the natural logarithm (base-e logarithm) of x.
There is no range limit on the argument or return value.
Range:double log10(double
x);
Returns the common logarithm (base-10 logarithm) of x.
There is no range limit on the argument or return value.
Range:double modf(double
x, double *
integer);
Breaks the floating-point number x into integer and fraction components.
The returned value is the fraction component (part after the decimal), and sets integer to the integer component.
There is no range limit on the argument or return value.
Range:double pow(double
x, double
y);
Returns x raised to the power of y.
x cannot be negative if y is a fractional value. x cannot be zero if y is less than or equal to zero.
Range:double sqrt(double
x);
Returns the square root of x.
The argument cannot be negative. The returned value is always positive.
Range:double ceil(double
x);
Returns the smallest integer value greater than or equal to x.
There is no range limit on the argument or return value.
Range:double fabs(double
x);
Returns the absolute value of x (a negative value becomes positive, positive value is unchanged).
There is no range limit on the argument. The return value is always positive.
Range:double floor(double
x);
Returns the largest integer value less than or equal to x.
There is no range limit on the argument or return value.
Range:double fmod(double
x, double
y);
Returns the remainder of x divided by y.
There is no range limit on the return value. If y is zero, then either a range error will occur or the function will return zero (implementation-defined).
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