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An Implementation of J

An explanation is provided for significant names in the system. Names spelled with majuscules denote defined types (typedef) or #define constants and macros; those spelled with minuscules denote C functions and variables.

Each entry has a name, its frequency of occurrence, and a brief description.

A B        1157  	The data type of an array; the data type of BOX array elements <<BR>>
a          1883  	The left argument of a verb <<BR>>
a0j1          9  	The complex atom 0j1
ainf         14 	The floating point atom _
AN(x)       759 	The n part of an array (the number of atoms in the value part)
apv(n,b,m)   96  	The arithmetic progression vector b+m*i.n
AN(x)       759 	The n part of an array; the number of atoms in the value part
AR(x)       581 	The r part of an array; the rank of an array
AS(x)       477 	The s part of an array; the shape of an array
ASSERT(p,e) 822 	Signal error e if proposition p is not true
AT(x)       733 	The t part of an array; the type of an array
B           706 	The data type of B01 array elements
B01	    160 	The type of a Boolean array
bp(t)        92 	The number of bytes per atom of type t
C           566 	The data type of LIT array elements
cstr(s)	     93 	A string with value the characters in the 0-terminated string s
DO(n,stmt)  905 	Execute n times the statement stmt, with local variable i running from 0 to n-1
EPILOG(x)    82 	Free all temporary storage used since the last PROLOG, then return x as a result
F1(f)       705 	Define f as a monadic verb or an adverb
F2(f)       326 	Define f as a dyadic verb or a conjunction
GA(t,n,r,s) 583 	Create an array of type t of rank r and shape s, with n atoms
I          1537 	The data type in C of a full-word integer
iv0	     17 	,2-2, the integer vector 0
iv1	     18 	,2-1, the integer vector 1
jt         2557 	Points to a structure of all the global variables for a J instance
LIT	    566 	The type of a literal (character) array (CHAR conflicts with C usage)
mtm	     44 	The empty matrix i.0 0
mtv	     73 	The empty vector i.0
neg1         22 	The integer atom _1
one          98 	The Boolean atom 1
pie	      5 	The floating point atom p (pi conflicts with C usage)
PROLOG       85 	Establish a checkpoint for temporary storage usage
RE(x)       220 	Return 0 if an error is signalled in executing x
RZ(x)      1537 	Return 0 if x is 0
sc(k)       217 	An integer atom with value k (equivalent to sc4(INT,k))
sc4(t,k)      5 	An atom of type t with 4-byte value k
scc(c)       17 	A literal atom with value c
scf(x)       26 	A floating point atom with value x
str(n,s)     52 	A string (literal list) of length n with value the characters pointed to by s
two	     24 	The integer atom 2
v1(k)        15 	The integer vector ,k
v2(a,b)      72 	The integer vector a,b
vec(t,n,v)   81 	A vector of length n of type t, with values pointed to by v
vi(x)        45 	"Verify integer", convert x to integer
w          3207 	The right argument of a verb
zero        129 	The Boolean atom 0

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