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any

Test whether at least one of equations and inequalities represented as elements of symbolic array is valid

Description

example

any(A) tests whether at least one element of A returns logical 1 (true). If A is a matrix, any tests elements of each column. If A is a multidimensional array, any tests elements along one dimension.

example

any(A,dim) tests along the dimension of A specified by dim.

Examples

Test Vector of Symbolic Conditions

Create vector V that contains the symbolic equation and inequalities as its elements:

syms x real
V = [x ~= x + 1, abs(x) >= 0, x == x];

Use any to test whether at least one of them is valid for all values of x:

any(V)
ans =
  logical
   1

Test Matrix of Symbolic Conditions

Create this matrix of symbolic equations and inequalities:

syms x real
M = [x == 2*x, x == abs(x); abs(x) >= 0, x == 2*x]
M =
[    x == 2*x, x == abs(x)]
[ 0 <= abs(x),    x == 2*x]

Use any to test equations and inequalities of this matrix. By default, any tests whether any element of each column is valid for all possible values of variables. If at least one equation or inequality in the column is valid (returns logical 1), then any returns logical 1 for that column. Otherwise, it returns logical 0 for the column. Thus, it returns 1 for the first column and 0 for the second column:

any(M)
ans =
  1×2 logical array
   1   0

Specify Dimension to Test Along

Create this matrix of symbolic equations and inequalities:

syms x real
M = [x == 2*x, x == abs(x); abs(x) >= 0, x == 2*x]
M =
[    x == 2*x, x == abs(x)]
[ 0 <= abs(x),    x == 2*x]

For matrices and multidimensional arrays, any can test elements along the specified dimension. To specify the dimension, use the second argument of any. For example, to test elements of each column of a matrix, use the value 1 as the second argument:

any(M, 1)
ans =
  1×2 logical array
   1   0

To test elements of each row, use the value 2 as the second argument:

any(M, 2)
ans =
  2×1 logical array
   0
   1

Test Arrays with Numeric Values

Test whether any element of this vector returns logical 1. Note that any also converts all numeric values outside equations and inequalities to logical 1s and 0s. The numeric value 0 becomes logical 0:

syms x
any([0, x == x + 1])
ans =
  logical
   0

All nonzero numeric values, including negative and complex values, become logical 1s:

any([-4 + i, x == x + 1])
ans =
  logical
   1

Input Arguments

collapse all

Input, specified as a symbolic array. For example, it can be an array of symbolic equations, inequalities, or logical expressions with symbolic subexpressions.

Dimension, specified as an integer. For example, if A is a matrix, any(A,1) tests elements of each column and returns a row vector of logical 1s and 0s. any(A,2) tests elements of each row and returns a column vector of logical 1s and 0s.

Tips

  • If A is an empty symbolic array, any(A) returns logical 0.

  • If some elements of A are just numeric values (not equations or inequalities), any converts these values as follows. All nonzero numeric values become logical 1. The value 0 becomes logical 0.

  • If A is a vector and any of its elements returns logical 1, any(A) returns logical 1. If all elements are zero, any(A) returns logical 0.

  • If A is a multidimensional array, any(A) treats the values along the first dimension that is not equal to 1 (non-singleton dimension) as vectors, returning logical 1 or 0 for each vector.

Version History

Introduced in R2012a

See Also

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