spec
Software for Diffraction
2.4.5.1. - Math Functions
exp(x), exp10(x)-
Returns
exand
10xrespectively.
log(x), log10(x)-
Returns
the natural logarithm and the base 10 logarithm of
x
respectively.
sqrt(x)-
Returns the square root of
x.
pow(x, y)-
Returns
xy.
fabs(x)-
Returns the absolute value of
x.
int(x)-
Returns the integer part of
x.
The integer part is formed by truncation towards zero.
rand()-
Returns a random integer between 0 and 32767.
rand(x)- If
x
is positive,
returns a random integer between 0 and
x,
inclusive.
If
x
is negative,
returns a random integer between
-x
and
x,
inclusive.
Values of
x
greater than 32767 or
less than -16383
are set to those limits.
If
x
is zero, zero is returned.
The C-library
rand()
function is used to obtain the values.
The seed is set to the time of day on the first call.
The randomness (or lack thereof)
of the numbers obtained is due to the C library
implementation.
srand(seed)-
Sets the seed value for the random
number generator used by the
rand()
function to the integer value
seed.
This function
allows the same sequence of random numbers to be
generated reproducibly by resetting the seed to the same value.
sin(x), cos(x), tan(x)-
Returns the sine, cosine and tangent, respectively, of the argument
x,
which must be in radians.
asin(x), acos(x), atan(x)-
Returns the arc sine, arc cosine and arc tangent, respectively, of the
argument
x.
The return value is in radians.
asin() and
atan() return values in the range -π/2 to π/2,
while
acos() returns values from 0 to π.
atan2(y, x)-
Returns the arc tangent of
y/x
using the signs of the arguments to determine the quadrant of the
return value.
The return value is in the range -π to π.
Having both
y
and
x
zero is an error.
