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Sequences

A sequence is a finite or infinite list of objects. The objects are numbered starting with 0.

There are a number of different kinds of sequence, but these are considered to be different ways of implementing the same abstract sequence type.

Higher-order arrays are considered to be sequences of sequences. (But ...)

A vector can be constructed with the [] constructor:

Q2> [[2 3 4] [5 6 7 4+4]]
2 3 4
5 6 7 8

Indexing uses an implicit "adjacency" operator, just like function calls:

Q1> [3 4 5] 2
5

size seq

Function

Returns the number of elements in seq: size [3 4 5] is 3.

seq length

Function

Returns the number of elements in seq: [3 4 5] length is 3.

Q vector N

Function

Allocate an updatable fixed-length vector of length N. Initialize the elements using the sequence Q. Default value for N is the Q length.

• Indexing:
• Selection:
• Truncation:
• Enumerations:
• Strings: A string is a sequence of characters.
• Files: Treat file system objects as strings.
• Cyclic: Cyclic infinite sequences
• Lazy vectors:
• Re-structuring: Operations for re-structuring sequences.