'''Purpose:''' Provide help on specific math functions in Tcl as built in in the [expr] command.

   * [abs]
   * [atan]
   * [atan2]
   * [hypot]
   * [rand]
   * [sqrt]
   * [srand]

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See also:

   * [pi]

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[Category command] | [Category Mathematics] | [Importing expr functions]