XploRe Help : diff

Keywords - Function groups - @ A B C D E F G H I J K L M N O P Q R S T U V W X Y Z

Library:	xplore
See also:	tdiff

Quantlet:		diff
Description:		computes first differences (along the rows) of an array.

Usage:	`dx = diff(x)`
Input:
	`x`	d1 x d2 x ... x dn array
Output:
	`dx`	(d1-1) x d2 x ... x dn array, first differences along the rows of x.

Example:

library("xplore") x =(1:4)|6 diff(x)

Result:

Contents of dx
[1,]        1
[2,]        1
[3,]        1
[4,]        2

Example:

library("xplore") x = matrix(3, 2, 2) x[1, 1, 1] = 2 x[2, 2, 2] = 3 diff(x)

Result:

Contents of dx
[,,1,1,1,1,1,1]
[1,]       -1        0
[2,]        0        0
[,,2,1,1,1,1,1]
[1,]        0        2
[2,]        0       -2

Author: MD*Tech, 20021120 license MD*Tech