Mat for Beginners
Mat (M) is short for matrix. A matrix is another word for an array. An array of variables in this case. An array is a series of variables.
Mat A would refer to the whole array of A(1) to A(10) (if 10 is the highest item in the array)
each item in the array can contain a different value. for example
A(1)=10 A(2)=30 A(3)=25 A(4)=40
A mat statement is refer to the whole array, for example:
PRINT MAT A
returns the following:
10 30 25 40
A mat statement can also be used to change how large the array is, for example:
changes the array to have 5 items in it. Then, after executing MAT A(5) and typing:
PRINT MAT A
you would get
10 30 25 40 0
The 5th item was never set to anything, so A(5) returns a 0.
A mat statement can also refer to a range within an array, for example
PRINT MAT A(2:4)
30 25 40
Arrays can be sorted, which changes the order of the items contained within the arrays. For example, to sort an array in ascending order:
0 10 25 30 40
Arrays can also have more than one dimension.
X(1,1)=5 X(1,2)=10 X(2,1)=15 X(2,2)=20
These are easiest to picture like a spread sheet with the two numbers identifying which cell a value is contained in (or like X and Y on a graph). Arrays can have up to 9 dimensions.