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Asymptote has built-in versions of the standard libm mathematical
real(real) functions sin, cos, tan, asin,
acos, atan, exp, log, pow10,
log10, sinh, cosh, tanh, asinh,
acosh, atanh, sqrt, cbrt, fabs,
as well as the identity function identity.
Asymptote also defines the order n Bessel functions of
the first kind J(int n, real) and second kind
Y(int n, real), as well as the gamma function gamma,
the error function erf, and the complementary error function
erfc. The standard real(real, real) functions atan2,
hypot, fmod, remainder are also included.
The functions degrees(real radians) and radians(real degrees)
can be used to convert between radians and degrees. The function
Degrees(real radians) returns the angle in degrees in the
interval [0,360).
For convenience, Asymptote defines variants Sin,
Cos, Tan, aSin, aCos, and aTan of
the standard trigonometric functions using degrees rather than radians.
The functions floor, ceil, and round differ from
their usual definitions in that they all return an int value rather than
a real (since that is normally what one wants).
The functions Floor, Ceil, and Round are
respectively similar, except that if the result cannot be converted
to a valid int, they return intMax
for positive arguments and -intMax for negative arguments,
rather than generating an integer overflow.
We also define a function sgn, which returns the sign of its
real argument as an integer (-1, 0, or 1).
There is an abs(int) function, as well as an abs(real) function
(equivalent to fabs(real)) and an abs(pair) function
(equivalent to length(pair)).
Random numbers can be seeded with srand(int) and generated with
the int rand() function, which returns a random integer between 0
and the integer randMax. A Gaussian random number generator
Gaussrand and a collection of statistics routines, including
histogram, are provided in the base file stats.asy.
When configured with the GNU Scientific Library (GSL), available from
http://www.gnu.org/software/gsl/,
Asymptote contains an internal module gsl that
defines the airy functions Ai(real),
Bi(real), Ai_deriv(real), Bi_deriv(real),
zero_Ai(int), zero_Bi(int),
zero_Ai_deriv(int), zero_Bi_deriv(int), the Bessel functions
I(int, real), K(int, real), j(int, real),
y(int, real), i_scaled(int, real), k_scaled(int, real),
J(real, real), Y(real, real), I(real, real),
K(real, real), zero_J(real, int), the elliptic functions
F(real, real), E(real, real), and P(real, real),
the exponential/trigonometric integrals Ei, Si, and Ci,
the Legendre polynomials Pl(int, real), and the Riemann zeta
function zeta(real). For example, to compute the sine integral
Si of 1.0:
import gsl; write(Si(1.0));