# The definition of “vector” in math and physics

• B
I'm learning APL and this is how a vector is defined https://tryapl.org:

All data resides in arrays. An array is a rectangular collection of numbers, characters and arrays, arranged along zero or more axes. We can use more specific terms for some arrays, like a single number is a scalar, a list is a vector, and 2D arrays are matrices. Vectors can be formed by just placing elements next to each other:​

I see that in math a list of numbers is called a vector.

In physics a vector is a directed magnitude. So vector in physics is a set of only two numbers. One of these numbers is interpreted as magnitude and the other is interpreted as direction.

My question is: Is the above description correct?

Orodruin
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So vector in physics is a set of only two numbers. One of these numbers is interpreted as magnitude and the other is interpreted as direction.
This is not a correct conclusion. Direction cannot be described by a single number (unless you are just looking at two dimensions).

jbriggs444
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Vectors are more formally treated in a discipline known as "linear algebra". It turns out that the ability to treat a vector as a one dimensional array of numbers can then be traced to being able to identify a "basis" for a vector space. Individual vectors within the space can then be identified with unique linear combinations of basis vectors and the linear combination can [sometimes] be described as a one dimensional array of numbers.

https://en.wikipedia.org/wiki/Vector_space

Stephen Tashi