IsVector

Tests whether list is a rank-1 List, optionally with every element satisfying test.

✓ checked against that system · ! checked, with disagreements (hover a chip)Wolfram LanguageVectorQ✓↗

IsVector(list)True if list is a List none of whose elements is itself a List

IsVector(list, test)as above, and test holds of every element

Typed signatures

Type	Package	Applies
(any, function?) -> boolean	combinatorics	always

Domain: Collections

Details

• A List containing a List (even a ragged one) is a matrix shape, not a vector — False.
• A lazy ordered collection such as $Range(1, 10)$ stands for the List it evaluates to.
• test is applied via Apply, same calling convention as a Function literal passed to Select/Map.

Examples

Basic #

live ↗

In$\mathrm{IsVector}(\bigl\lbrack1, 2, 3\bigr\rbrack)$Out$\mathrm{True}$

A flat list is a vector, whatever its entries

live ↗

In$\mathrm{IsVector}(\bigl\lbrack a, b, c\bigr\rbrack)$Out$\mathrm{True}$

A column of one-element lists is a matrix, not a vector

live ↗

In$\mathrm{IsVector}(\bigl\lbrack\bigl\lbrack1\bigr\rbrack, \bigl\lbrack2\bigr\rbrack\bigr\rbrack)$Out$\mathrm{False}$

An undefined symbol is not known to be a vector

live ↗

In$\mathrm{IsVector}(\mathrm{vector})$Out$\mathrm{False}$

Scope #

live ↗

In$\mathrm{IsVector}(\bigl\lbrack\bigl\lbrack1, 2\bigr\rbrack, \bigl\lbrack3, 4\bigr\rbrack\bigr\rbrack)$Out$\mathrm{False}$

live ↗

In$\mathrm{IsVector}(3)$Out$\mathrm{False}$

live ↗

In$\mathrm{IsVector}(\bigl\lbrack2, 4, 6\bigr\rbrack, \mathrm{IsEven})$Out$\mathrm{True}$

live ↗

In$\mathrm{IsVector}(\bigl\lbrack2, 3, 6\bigr\rbrack, \mathrm{IsEven})$Out$\mathrm{False}$

The optional test must hold for every entry; exact integers fail it

live ↗

In$\mathrm{IsVector}(1..10, \mathrm{IsMachineNumber})$Out$\mathrm{False}$

live ↗

In$\mathrm{IsVector}(1..10, \mathrm{IsInteger})$Out$\mathrm{True}$

live ↗

In$\mathrm{IsVector}(N(1..10), \mathrm{IsMachineNumber})$Out$\mathrm{True}$

live ↗

In$\mathrm{IsVector}(\bigl\lbrack1, π, \sin(1), \sqrt{2}\bigr\rbrack, \operatorname{\_1}↦\mathrm{IsNumeric}(\operatorname{\_1})∧\Im(\operatorname{\_1})=0)$Out$\mathrm{True}$

Properties #

Undefined symbols are not known to be vectors

live ↗

In$\bigl\lbrack\mathrm{IsVector}(\mathrm{vec}), \mathrm{IsVector}(\mathrm{expr})\bigr\rbrack$Out$\bigl\lbrack\mathrm{False}, \mathrm{False}\bigr\rbrack$

About

Examples	13
Checked against	Wolfram Language 13 agree
Crosswalk	Wolfram Language

See also: IsMatrix, IsArray