To ease reproducibility, the variable *RANDOM-STATE* is initialized to the same value on each invocation, so that

$ clisp -norc -x '(RANDOM 1s0)'

will always print the same number.

If you want a new random state on each invocation, you can arrange for that by using init function:

$ clisp -norc -x '(EXT:SAVEINITMEM "foo" :init-function (LAMBDA () (SETQ *RANDOM-STATE* (MAKE-RANDOM-STATE T))))'
$ clisp -norc -M foo.mem -x '(RANDOM 1s0)'

or by placing (SETQ *RANDOM-STATE* (MAKE-RANDOM-STATE T)) into your RC file.

Function EXT:! (EXT:! n) returns the factorial of n, n being a nonnegative INTEGER.

Function EXT:EXQUO. (EXT:EXQUO x y) returns the integer quotient x/y of two integers x,y, and SIGNALs an ERROR when the quotient is not integer. (This is more efficient than /.)

Function EXT:XGCD. (EXT:XGCD x1 ... xn) returns the values l, k1, ..., kn, where l is the greatest common divisor of the integers x1, ..., xn, and k1, ..., kn are the integer coefficients such that

l = (GCD x1 ... xn)
  = (+ (* k1 x1) ... (* kn xn))

Function EXT:MOD-EXPT. (EXT:MOD-EXPT k l m) is equivalent to (MOD (EXPT k l) m) except it is more efficient for very large arguments.

Function EXPT. (EXPT base exponent) is not very precise if exponent has a large absolute value.

Function LOG. (LOG number base) SIGNALs an ERROR if base = 1.

Constant PI. The value of PI is a LONG-FLOAT with the precision given by (EXT:LONG-FLOAT-DIGITS). When this precision is changed, the value of PI is automatically recomputed. Therefore PI is not a constant variable.

Function UPGRADED-COMPLEX-PART-TYPE. When the argument is not a recognizable subtype or REAL, UPGRADED-COMPLEX-PART-TYPE SIGNALs an ERROR, otherwise it returns its argument (even though a COMPLEX number in CLISP can always have REALPART and IMAGPART of any type) because it allows the most precise type inference.

Variable CUSTOM:*DEFAULT-FLOAT-FORMAT*. When rational numbers are to be converted to floats (due to FLOAT, COERCE, SQRT or a transcendental function), the result type is given by the variable CUSTOM:*DEFAULT-FLOAT-FORMAT*.

Macro EXT:WITHOUT-FLOATING-POINT-UNDERFLOW. The macro (EXT:WITHOUT-FLOATING-POINT-UNDERFLOW {form}*) executes the forms, with errors of type FLOATING-POINT-UNDERFLOW inhibited. Floating point operations will silently return zero instead of SIGNALing an ERROR of type FLOATING-POINT-UNDERFLOW.

Condition FLOATING-POINT-INVALID-OPERATION. This CONDITION is never SIGNALed by CLISP.

Condition FLOATING-POINT-INEXACT. This CONDITION is never SIGNALed by CLISP.

FLOAT-RADIX always returns 2.

(FLOAT-DIGITS number digits) coerces number (a REAL) to a floating point number with at least digits mantissa digits. The following always evaluates to T:

(>= (FLOAT-DIGITS (FLOAT-DIGITS number digits)) digits)

BIGNUMs are limited in size. Their maximum size is 32*(216-2)=2097088 bits. The largest representable BIGNUM is therefore 22097088-1.

Together with PI, the other LONG-FLOAT constants

are recomputed whenever (EXT:LONG-FLOAT-DIGITS) is SETFed. They are not constant variables.