Difference between revisions of "Compose"

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m (moved Composition to Compose: Originally mis-named -- need to distinguish from {dieresiscircle} (Composition))
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* The derived function from the form <apll><i>a</i>∘<i>b</i></apll> always signals a <apll>SYNTAX ERROR</apll>.
 
* The derived function from the form <apll><i>a</i>∘<i>b</i></apll> always signals a <apll>SYNTAX ERROR</apll>.
 +
<p>
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Compose can be useful for function assignment (but enclosing parentheses are necessary).
 +
<br/>
 +
For example<br/>
 +
<apll>
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&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;p1←(1∘+¯2∘π) ⍝ 1 more than the Nth prime number<br/>
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&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;p1 ⍳9<br/>
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3 4 6 8 12 14 18 20 24
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</apll>

Revision as of 13:56, 1 December 2016

In the following descriptions, f and g represent functions and a and b represent variables.

  • The form fg may be used both monadically and dyadically.
Monadic: Z←fgR is identical to Z←fgR.
Dyadic: Z←LfgR is identical to Z←LfgR.
  • The form f∘b may be used monadically only.
Monadic: Z←(fb) R is identical to Z←R f b.
Note that parentheses are required around the function to avoid interpreting b R as a strand.
  • The form ag may be used monadically only.
Monadic: Z←agR is identical to Z←a g R.
  • The derived function from the form ab always signals a SYNTAX ERROR.

Compose can be useful for function assignment (but enclosing parentheses are necessary).
For example
      p1←(1∘+¯2∘π) ⍝ 1 more than the Nth prime number
      p1 ⍳9
3 4 6 8 12 14 18 20 24