HELP INT R. J. Duncan, September 1989 Functions on integers. CONTENTS - (Use g to access required sections) -- The Int Module -- Integer Functions -- The Int Module ----------------------------------------------------- signature Int structure Int : Int The structure -Int- is a built-in structure of PML which defines a collection of useful functions on integers. It has the following signature: signature Int = sig exception Power val sign : int -> int val max : int -> int -> int val min : int -> int -> int val power : int -> int -> int val gcd : int -> int -> int val lcm : int -> int -> int val ** : int * int -> int val quot : int * int -> int val rem : int * int -> int end For the definition of the integer type (int) see HELP * STDTYPES. For the basic mathematical operators see HELP * STDVALUES. For a similar set of functions on real numbers see HELP * REAL. -- Integer Functions -------------------------------------------------- val sign (n : int) : int Returns the sign of the integer -n-, i.e., one of the integers ~1, 0, or 1 according to whether -n- is less than, equal to or greater than zero. val max (n1 : int) (n2 : int) : int Returns the greater of the integers -n1- and -n2-. val min (n1 : int) (n2 : int) : int Returns the lesser of the integers -n1- and -n2-. infix 7 quot rem val (i : int) quot (d : int) : int val (i : int) rem (d : int) : int Integer division and remainder. Given val (q, r) = (i quot d, i rem d) then the relationship i = d * q + r holds, where abs(d * q) <= abs(i) (i.e. the division rounds towards zero). For both -quot- and -rem-, the standard exception -Div- is raised if -d- is zero. The functions -quot- and -rem- are typically faster than (though slightly different to) the standard integer division operators -div- and -mod- described in HELP * STDVALUES. exception Power infix 8 ** val (n : int) ** (m : int) : int val power (n : int) (m : int) : int Returns the value of -n- raised to the power -m-. Raises the exception -Power- if -m- is less than zero. For a more general power function see HELP * REAL/power. val gcd (n1 : int) (n2 : int) : int Returns the greatest common divisor of the integers -n1- and -n2-. val lcm (n1 : int) (n2 : int) : int Returns the least common multiple of the integers -n1- and -n2-. --- C.all/pml/help/int --- Copyright University of Sussex 1991. All rights reserved. ----------