Strand Assignment: Difference between revisions

Revision as of 09:20, 9 April 2008

(A₁ A₂ ... A_n)←R

Assigns the successive items of R to the names.

A₁ A₂ ... A_n are assignable names, R is a scalar or vector.

If 1<⍴⍴R, signal a RANK ERROR.

If R is a scalar or one element vector, its item is assigned to each name, as in A_i←⊃⍬⍴R.

Otherwise, assume there are n names in the list:

If n≠⍴R, signal a LENGTH ERROR.

Otherwise, each successive item of R is assigned to each successive name, as in A_i←i⊃R.

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

Note that (A B)←B A is a simple and efficient way to swap the values of the two names.

@@ Line 34: / Line 34: @@
 <br />
 <br />
-For example, <apl size="large">(A B C){is}{enclose}{iota}3</apl> is the same as <apl size="large">A{is}B{is}C{is}{iota}3</apl>.  In contrast, <apl size="large">(A B C){is}{iota}3</apl> is the same as <apl size="large">A{is}1 {diamond} B{is}2 {diamond} C{is}3</apl>.<br />Also, <apl size="large">(A B C){is}(1 2) 'abc' 1.1</apl> is the same as <apl size="large">A{is}1 2 {diamond} B{is}'abc' {diamond} C{is}1.1</apl>, and <apl size="large">(A B){is}B A</apl> is a simple and efficient way to swap the values of the two names.
+For example, <apl size="large">(A B C){is}{enclose}{iota}3</apl> is shorthand for <apl size="large">A{is}B{is}C{is}{iota}3</apl>.  In contrast, <apl size="large">(A B C){is}{iota}3</apl> is shorthand for <apl size="large">A{is}1 {diamond} B{is}2 {diamond} C{is}3</apl>.
+Note that <apl size="large">(A B){is}B A</apl> is a simple and efficient way to swap the values of the two names.