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Building Matrices
Syntax list of values ]
list of values }
See Also elements , fill , str2mat

Description
Builds a matrix from other matrices.

Brackets
Brackets ([ ]) combine matrices that have the same row dimension. The column dimension of the resulting matrix is the sum of the widths of the combined matrices.

Tutorial
If you enter
     x = [1, 2, 3]
     y = [4, 5]
     print [x, y]
O-Matrix will respond
     [ 1 , 2 , 3 , 4 , 5 ]
If you enter
     x = {[1, 2], [6, 7]}
     y = {[3, 4, 5], [8, 9, 10]}
     [x, y]
O-Matrix will respond
     {
     [ 1 , 2 , 3 , 4 , 5 ]
     [ 6 , 7 , 8 , 9 , 10 ]
     }

Braces
Braces ({ }) combine matrices that have the same column dimension. The row dimension of the resulting matrix is the sum of the heights of the combined matrices. If the values are character matrices, they need not have the same column dimension. The resulting matrix takes on the same width as the widest row. (Spaces are used to fill in the shorter rows).

Tutorial
If you enter
     x = {1, 2}
     y = 3
     {x, y}
O-Matrix will respond
     {
     1
     2
     3
     }
If you enter
     x = {[1, 2], [3, 4]}
     y = [5, 6]
     {x, y}
O-Matrix will respond
     {
     [ 1 , 2 ]
     [ 3 , 4 ]
     [ 5 , 6 ]
     }
If you enter
     x = {"red", "blue"}
     print x
O-Matrix will respond
     red
     blue
Note that the column dimension of x is 4.

Empty Matrices
If there are no expressions within the brackets or braces, the result is a logical empty matrix with both its row and column dimension equal to zero. If you enter
     x = { }
     print type(x), rowdim(x), "by", coldim(x), "matrix"
O-Matrix will respond
     logical 0 by 0 matrix
If you want to clear the memory reserved for a variable and guard against its value being used by mistake, you should use novalue instead of an empty matrix.

When using the brackets and braces to combine matrices, it is admissible for some of the matrices to be 0 by 0 matrices. Such matrices do not add any elements during the combine operation. If you enter
     x = []
     y = {1, x, 2}
O-Matrix will respond
     {
     1
     2
     }

Reference
If the value types do not agree, O-Matrix will coerce the values as detailed in the coercion section.