For the 1999 film, see The Matrix.
A matrix (pl.: "matrices," Latin origin) is a complex ordering, in deliberate fashion, of numerals. In mathematics, a "matrix" is a regular grid of numbers, which may be manipulated and solved through intermediate-level algebra. Matrix algebra is usually taught in sophomore high school level mathematics.
More formally, a matrix is an example of a rank-2 tensor.
Alternately, a matrix may also be a complex ordering of a group of equivalent objects, especially where the order is imposed to gain incidental benefit from the synergy of the networked objects.
In mathematics, matrices can be manipulated in a variety of ways, including addition and multiplication.
To add two matrices, one would add their respective elements. For example:
would equal
To multiply two matrices, use the rule for finding the product of two matrices:
However, not every pair of matrices can be multiplied. In order for matrices and
to be compatible for multiplication, the number of columns in
must equal the number of rows in
. If
is an
matrix and
is an
matrix, the product matrix
will have
rows and
columns.
Matrix multiplication is associative. However, matrix multiplication is not commutative. That is, it is possible for .
The identity matrix
satisfies the property:
for all matrices
.
Moreover, every square matrix with nonzero determinant has an inverse matrix
such that
This means that for every positive integer , the set of all
matrices with nonzero determinant form a group under matrix multiplication. This group is known as the general linear group
.
Categories: [Linear Algebra] [Computers]