HELP NEWARRAY updated Mark Rubinstein October 1985 A. Sloman April 1989 See HELP * ARRAYS for an introduction to arrays in POP-11. newarrary() -> newarrary(, ) -> newarrary(, ) -> The simplest way to create an array in POP-11 is to use NEWARRAY, which creates an array capable of holding any POPLOG data-types. newarray(, ) -> E.g. newarray([1 5 1 10], 0) -> aa; creates a two dimensional 5 by 10 array each of whose elements is 0. The elements of the array are accessed or updated using two integers the first in the range 1 to 5, the second in the range 1 to 10, as specified in the argument. The syntax used is the same as if the array were a procedure (which in fact it is in POP-11). So: aa(3,5) => ** 0 66 -> aa(3,5); aa(3,5) => ** 66 [a list ] -> aa(4,2); aa(4,2) => ** [a list] NB: the second argument of NEWARRAY mus not be a list as it will then be taken to be the . See the use of initialising procedures below. If the second argument is missing, it defaults to the word "undef". newarray([1 10 1 10]) -> aa; This creates a ten by ten array, both of whose subscripts vary in the range one to ten, all the elements being undef. (See HELP *UNDEF) aa(5,5) => ** undef newarray([-5 15]) Creates a one dimensional array whose subscript varies in the range -5 to 15. Instead of an initial value, the second argument to NEWARRAY may be a procedure which computes the value on the basis of the subscripts. The procedure must take as many arguments as the dimensions of the arrary. Thus, to create a 3 by 5 array whose elements are the product of the susbcripts do: newarray([1 3 1 5], nonop *) -> aa; Then: aa(2,5) => ** 10 aa(3,2) => ** 6 Or to create an array containing a list of the subscripts: newarray([-5 5 -10 10], procedure(x,y); [^x ^y] endprocedure) -> aa; aa(-3,5) => ** [-3 5] There is a more powerful procedure *NEWANYARRAY that can be used to create 'packed' arrays corresponding to any vector data-type, e.g. it could create a compact array of bits, or of 4 bit integers. NEWARRAY coudl have been defined in terms of it thus: vars newarray; newanyarray(%initv, subscrv%) -> newarray; See HELP * NEWANYARRAY for details on setting up initial component values. See REF * DATA - POP-11 data types and accessing procedures REF * KEYS - data keys associated with a data class REF * VECTORS - VECTOR types in POP-11 HELP * VECTORCLASS - Defining new vector types HELP * CLASSES - classes and procedures associated with a class See also HELP * BOUNDSLIST, *ARRAYVECTOR, *ISARRAY --- C.all/help/newarray --- Copyright University of Sussex 1989. All rights reserved. ----------