Juxtaposition means combine in the obvious way: Difference between revisions
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In an expression, putting two things immediately next to each other usually means that they should be combined in some way. It's usually implicit that the combination operation should be clear from the context. | In an expression, putting two things immediately next to each other usually means that they should be combined in some way. It's usually implicit that the combination operation should be clear from the context. | ||
==Examples== | |||
* [[Missing multiplication symbol|Multiplication]]: \(ab = a \times b\). | * [[Missing multiplication symbol|Multiplication]]: \(ab = a \times b\). | ||
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* Group operation: when \(x,y \in G = (X,\star)\), \(xy = x \star y\). | * Group operation: when \(x,y \in G = (X,\star)\), \(xy = x \star y\). | ||
* A linear transformation: \(\mathrm{A}\mathbf{v}\). (I've never seen \(\mathrm{A} \times \mathbf{v}\) or \(\mathrm{A} \cdot \mathbf{v}\) for matrix-vector product) | * A linear transformation: \(\mathrm{A}\mathbf{v}\). (I've never seen \(\mathrm{A} \times \mathbf{v}\) or \(\mathrm{A} \cdot \mathbf{v}\) for matrix-vector product) | ||
==Exceptions== | |||
* [[Matrix indices|Matrix indices written without a comma]]. | |||
Revision as of 15:02, 10 July 2021
In an expression, putting two things immediately next to each other usually means that they should be combined in some way. It's usually implicit that the combination operation should be clear from the context.
Examples
- Multiplication: \(ab = a \times b\).
- Function composition: \(fg(x) = f \circ g(x) = f(g(x))\).
- Function application: \(\sin x\).
- Group operation: when \(x,y \in G = (X,\star)\), \(xy = x \star y\).
- A linear transformation: \(\mathrm{A}\mathbf{v}\). (I've never seen \(\mathrm{A} \times \mathbf{v}\) or \(\mathrm{A} \cdot \mathbf{v}\) for matrix-vector product)
