Juxtaposition means combine in the obvious way: Difference between revisions

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[[Category:Unspoken conventions]]
[[Category:Ambiguities]]
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]]: \(ab = a \times b\).
* Function composition: \(fg(x) = f \circ g(x) = f(g(x))\).
* Function composition: \(fg(x) = f \circ g(x) = f(g(x))\).
* Group operation: when \(x,y \in G = (X,\star\)\), \(xy = x \star y\).
* [[Function application without parentheses|Function application]]: \(\sin x\).
* [[Function application without parentheses|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)
* 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]].

Latest revision as of 10:17, 16 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)

Exceptions