ComponentExpand
ComponentExpand[expr]
expands out array variables in expr in terms of indexed components.
ComponentExpand[expr,assum]
specifies dimensionality of variables using assumptions assum.
Details and Options
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- ComponentExpand can be used for rewriting symbolic array expressions in terms of indexed components.
- ComponentExpand returns the component-wise expression for a symbolic array expression.
- Array variables may be specified using VectorSymbol, MatrixSymbol, ArraySymbol or through assumptions.
- Assumptions should consist of domain specifications Element[a,dom], where dom may be Vectors[d], Matrices[{d1,d2}], Arrays[{d1,…,dk}] or a region.
- Array variables need to have explicit integer dimensions to be expanded.
- ComponentExpand replaces special symbolic arrays with explicit arrays and replaces vector inequalities with scalar inequalities.
- ComponentExpand has the option Assumptions, specifying default assumptions to be appended to assum.
- The default setting for the Assumptions option is $Assumptions.
- You can specify default assumptions for ComponentExpand using Assuming.
Examples
open allclose allBasic Examples (3)
Scope (5)
Array variables specified through ArraySymbol, MatrixSymbol and VectorSymbol:
Array variables specified through assumptions:
Expressions involving array variables:
Options (1)
Assumptions (1)
Use the assumptions argument to specify the dimensionality of v:
Use the Assumptions option:
Use Assuming to specify default assumptions:
Text
Wolfram Research (2025), ComponentExpand, Wolfram Language function, https://reference.wolfram.com/language/ref/ComponentExpand.html.
CMS
Wolfram Language. 2025. "ComponentExpand." Wolfram Language & System Documentation Center. Wolfram Research. https://reference.wolfram.com/language/ref/ComponentExpand.html.
APA
Wolfram Language. (2025). ComponentExpand. Wolfram Language & System Documentation Center. Retrieved from https://reference.wolfram.com/language/ref/ComponentExpand.html