 ## What is a matrix

A matrix is ​​a set of complex or real numbers arranged in a rectangular array. A matrix with real numbers is called a real matrix, and a matrix with elements is a complex matrix. A matrix with the number of rows and columns equal to n is called an n-th order matrix or an n-th order square matrix.

A number table of m rows and n columns arranged by m × n numbers aij is called a matrix of m rows and n columns, which is referred to as an m × n matrix. Referred to as: ## Relationship of scalar, vector, matrix, tensor

These 4 concepts are constantly rising in dimensionality. It is easier to understand the metaphorical explanation with the concept of point-line polyhedron:

• Point - scalar (Scalar
• Line - vectorvector
• Face-matrix
• Body - tensor ## Baidu Encyclopedia and Wikipedia

Baidu Encyclopedia version

In mathematics, a matrix is ​​a set of complex or real numbers arranged in a rectangular matrix, starting from the square matrix of coefficients and constants of the system of equations. This concept was first proposed by 19 century British mathematician Kelly.

Matrices are common tools in advanced algebra and are also commonly used in applied mathematics such as statistical analysis. In physics, matrices are used in circuit science, mechanics, optics, and quantum physics; in computer science, 3D animation requires matrix. The operation of the matrix is ​​an important issue in the field of numerical analysis. Decomposing a matrix into a simple matrix simplifies the operation of the matrix in both theoretical and practical applications. For some widely used and form-specific matrices, such as sparse matrices and quasi-diagonal matrices, there are specific fast arithmetic algorithms. For the development and application of matrix related theory, please refer to matrix theory. In the fields of astrophysics, quantum mechanics, etc., there are also infinite dimensional matrices, which is a generalization of matrices.