Details and Options
- AntisymmetricMatrixQ is also known as skew-symmetric.
- A matrix m is antisymmetric if m-Transpose[m].
- AntisymmetricMatrixQ works for symbolic as well as numerical matrices.
- The following options can be given:
SameTest Automatic function to test equality of expressions Tolerance Automatic tolerance for approximate numbers
- For exact and symbolic matrices, the option SameTest->f indicates that two entries mij and mkl are taken to be equal if f[mij,mkl] gives True.
- For approximate matrices, the option Tolerance->t can be used to indicate that all entries Abs[mij]≤t are taken to be zero.
- For matrix entries Abs[mij]>t, equality comparison is done except for the last bits, where is $MachineEpsilon for MachinePrecision matrices and for matrices of Precision .
Examplesopen allclose all
Basic Examples (2)
Basic Uses (6)
Use AntisymmetricMatrixQ with an arbitrary-precision matrix:
Use AntisymmetricMatrixQ with a symbolic matrix:
AntisymmetricMatrixQ works efficiently with large numerical matrices:
Adjust the option Tolerance to accept this matrix as antisymmetric:
Using Table generates an antisymmetric matrix:
SymmetrizedArray can generate matrices (and general arrays) with symmetries:
Properties & Relations (15)
AntiymmetricMatrixQ[x] trivially returns False for any x that is not a matrix:
A matrix is antisymmetric if m-Transpose[m]:
Use Diagonal to pick out the diagonal elements:
This equals the normalized difference between m and Transpose[m]:
Use SymmetricMatrixQ to test whether a matrix is symmetric:
MatrixExp[m] for real antisymmetric m is both orthogonal and unitary:
Use Eigenvalues to find eigenvalues:
CharacteristicPolynomial[m,x] contains only even powers of x:
Use Eigenvectors to find the necessarily complex-valued eigenvectors:
Det[m] for antisymmetric m of odd dimensions is zero:
Possible Issues (1)
AntisymmetricMatrixQ uses the definition for both real- and complex-valued matrices:
AntihermitianMatrixQ tests the condition for skew-adjoint matrices:
Wolfram Research (2014), AntisymmetricMatrixQ, Wolfram Language function, https://reference.wolfram.com/language/ref/AntisymmetricMatrixQ.html.
Wolfram Language. 2014. "AntisymmetricMatrixQ." Wolfram Language & System Documentation Center. Wolfram Research. https://reference.wolfram.com/language/ref/AntisymmetricMatrixQ.html.
Wolfram Language. (2014). AntisymmetricMatrixQ. Wolfram Language & System Documentation Center. Retrieved from https://reference.wolfram.com/language/ref/AntisymmetricMatrixQ.html