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The Function: Membership
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Monadic (One-Argument) Form
There is no monadic form.
Dyadic (Two-Argument) Form: Membership AEB
The membership function result is a 1 for each element of argument A that can be
found among the elements of argument B and a 0 for every element that cannot be
found. The shape of the result is the same as the shape of argument A.
Arguments A and B can be any scalar, vector, or array:

The .Function: Matrix Inverse, Matrix Divide a
The symbol is formed by overstriking the 0 and the i symbols.
Monadic (One-Argument) Form: Matrix Inverse B
The matrix inverse function inverts a nonsingular matrix or computes the pseudo-
inverse of a rectangular matrix. The result is a matrix. Argument B must be a
numeric matrix, and the number of columns must not exceed the number of rows.
The number of columns in the argument is the number of rows in the result, and
vice versa.
If argument B is a nonsingular matrix, OB is the inverse of B. If the matrix does
not have an inverse, then DOMAIN ERROR results:
If argument B is a rectangular matrix, HB is the pseudoinverse of the matrix (least
squares solution):
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Dyadic (Two-Argument) Form: Matrix Divide ABB
The matrix divide function solves one or more sets of linear equations with co-
efficient matrices. Argument B must be a numeric matrix. The number of columns
in B must not exceed the number of rows. Argument A must be a numeric vector or
a matrix. The length of the first coordinate of argument A must equal the length
of the first coordinate of argument B.
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