(3
The I Function: Index Generator, Index of
Monadic (One-Argument) Form: Index Generator I B
Dyadic (Two-Argument) Form: Index of A I B
The index offunction result is the index of the first occurrence in argument A of
the element(s1 in argument B. Argument A must be a vector. Argument B can be
a scalar, vector, or array. The result is the same shape as argument B. If the element
in argument B cannot be found in argument A, the value of the index for that ele-
ment is one greater than the largest index of A (nl0 + PA):
The index generator function result is a vector containing the first B integers, start-
ing with the index origin (see Dl0 system variable in Chapter 5). The argument can
be a nonnegative integer that is either a scalar or a single-element array.
5.t i 5 -Each of the generated integers is added to 5.
6 ‘7 8 9 10
Note: The result of the I function depends on the 010 system variable (see Chapter
5 for information on the 010 system variable).
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The r$ Function: Reverse, Rotate I".] Ic]
The r$ symbol is formed by overstriking the o symbol and the I symbol. A special
form of the function symbol ise, formed by overstriking the o symbol and the -
symbol.
Monadic (One-Argument) Form: Reverse $[I1 B
or r$B or eB
The reverse function reverses the elements of argument B. Argument B
can be any
expression.
89