Difference between revisions of "Determinant"
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[[category:Matrix Functions]] | [[category:Matrix Functions]] | ||
− | [[Category:Doc Status | + | [[category:Array-reducing functions]] |
+ | [[Category:Doc Status D]] <!-- For Lumina use, do not change --> | ||
− | Determinant( | + | ==Determinant(c, I, J)== |
− | The determinant of a matrix. | + | Computes the determinant of a square matrix, «c». Indexes «<code>I</code>» and «<code>J</code>» must be the same length, so that the matrix is square. |
+ | |||
+ | The determinant of a matrix is a useful value that is used heavily in linear algebra and matrix applications. The [[Invert|inverse]] of a matrix exists and is unique if and only if the determinant is non-zero. | ||
+ | |||
+ | Geometrically, the determinant can be viewed as the N-dimensional volume of the N-dimensional parallelepiped formed from the vectors in matrix «c». A parallelepiped in the N-dimensional generalization of a parallelogram (a 2-D parallelepiped is a parallelogram). Each vertex of the parallelepiped is obtained by taking a subset of the slices along «<code>J</code>» and adding them together. The empty subset is the origin. There are <code>2^N</code> subsets, where <code>N=[[Size]](J)</code>. | ||
+ | |||
+ | == Examples == | ||
+ | |||
+ | The determinant of the identity matrix is 1. | ||
+ | :<code>Determinant(I=J,I,J) → 1</code> | ||
+ | |||
+ | With <code>c</code> → [[image:Determinant_example1.png]], | ||
+ | :<code>Determinant(c,I,J)</code> → 15 | ||
+ | |||
+ | With <code>c</code> → [[image:Determinant_example2.png]], | ||
+ | :<code>Determinant(c,I,J)</code> → -114 - 68j | ||
+ | |||
+ | |||
+ | :<code>Variable Matrix :=</code> | ||
+ | :{| class="wikitable" | ||
+ | ! | ||
+ | ! colspan="5" |M ▶ | ||
+ | |- | ||
+ | !L ▼ | ||
+ | !1 | ||
+ | !2 | ||
+ | !3 | ||
+ | !4 | ||
+ | !5 | ||
+ | |- | ||
+ | !1 | ||
+ | |6 | ||
+ | |2 | ||
+ | |6 | ||
+ | |3 | ||
+ | |1 | ||
+ | |- | ||
+ | !2 | ||
+ | |2 | ||
+ | |4 | ||
+ | |3 | ||
+ | |1 | ||
+ | |3 | ||
+ | |- | ||
+ | !3 | ||
+ | |6 | ||
+ | |3 | ||
+ | |9 | ||
+ | |3 | ||
+ | |4 | ||
+ | |- | ||
+ | !4 | ||
+ | |3 | ||
+ | |1 | ||
+ | |3 | ||
+ | |8 | ||
+ | |4 | ||
+ | |- | ||
+ | !5 | ||
+ | |1 | ||
+ | |3 | ||
+ | |4 | ||
+ | |4 | ||
+ | |7 | ||
+ | |} | ||
+ | |||
+ | :<code>Determinant(Matrix,L,M) → 359</code> | ||
+ | |||
+ | ==See Also== | ||
+ | * [[MatrixMultiply]] | ||
+ | * [[Decompose]] | ||
+ | * [[Matrix functions]] | ||
+ | * [[:Category:Matrix Functions]] |
Latest revision as of 18:51, 24 March 2016
Determinant(c, I, J)
Computes the determinant of a square matrix, «c». Indexes «I
» and «J
» must be the same length, so that the matrix is square.
The determinant of a matrix is a useful value that is used heavily in linear algebra and matrix applications. The inverse of a matrix exists and is unique if and only if the determinant is non-zero.
Geometrically, the determinant can be viewed as the N-dimensional volume of the N-dimensional parallelepiped formed from the vectors in matrix «c». A parallelepiped in the N-dimensional generalization of a parallelogram (a 2-D parallelepiped is a parallelogram). Each vertex of the parallelepiped is obtained by taking a subset of the slices along «J
» and adding them together. The empty subset is the origin. There are 2^N
subsets, where N=Size(J)
.
Examples
The determinant of the identity matrix is 1.
Determinant(I=J,I,J) → 1
Determinant(c,I,J)
→ 15
Determinant(c,I,J)
→ -114 - 68j
Variable Matrix :=
M ▶ L ▼ 1 2 3 4 5 1 6 2 6 3 1 2 2 4 3 1 3 3 6 3 9 3 4 4 3 1 3 8 4 5 1 3 4 4 7
Determinant(Matrix,L,M) → 359
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