Modify Strand Assignment: Difference between revisions

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     <table border="0" cellpadding="5" cellspacing="0" summary="">
     <table border="0" cellpadding="5" cellspacing="0" summary="">
     <tr>
     <tr>
       <td><apll> (A<sub>1</sub> A<sub>2</sub> ... A<sub>n</sub>)<i>f</i>←R</apll></td>
       <td><apll>(A<sub>1</sub> A<sub>2</sub> ... A<sub>n</sub>)<i>f</i>←R</apll></td>
       <td></td>
       <td></td>
       <td></td>
       <td></td>

Latest revision as of 03:57, 12 April 2008

(A1 A2 ... An)f←R In general, assigns Ai←Aif i⊃R.
A1 A2 ... An are all names with existing values, f is an arbitrary dyadic function, and R is a scalar or vector.
If 1<⍴⍴R, signal a RANK ERROR.
If R is a scalar or one element vector, its item, in combination with the value of each name, is assigned to each name, as in Ai←Aif ⊃⍬⍴R.
Otherwise, assume there are n names in the list:
If n≠⍴R, signal a LENGTH ERROR.
Otherwise, each successive item of R, in combination with the value of each successive name, is assigned to each successive name, as in Ai←Aif i⊃R.


For example, (A B C)⍴←⊂⍳3 is shorthand for A←A⍴⍳3 ⋄ B←B⍴⍳3 ⋄ C←C⍴⍳3. In contrast, (A B C)⍴←⍳3 is shorthand for A←A⍴1 ⋄ B←B⍴2 ⋄ C←C⍴3.