Modify Strand Assignment
|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.