The number of items in a list is the product of the dimensions of a list. So, for example, if a list has the shape 2 3, it has six elements.
Also, as 1 is the identity element for multiplication, a list with no dimensions has one element. Or, as I like to think of it, atoms are what you put in lists, so they don't have any dimensions to impose on their container. (This is why >1;2;3 has just one dimension, while >1;2;,3 has two dimensions.) I have seen suggestions that J arrays ignore leading "1" dimensions (much like integers ignore leading "0" digits). However, this would introduce problems. To illustrate: given matrices x and y, the statement x *1 2 y would have a problem when x was shape 2 1 an y was shape 1 2. -- Raul ---------------------------------------------------------------------- For information about J forums see http://www.jsoftware.com/forums.htm
