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A comment on Linear Algebra: What matrices are. Parent comment

Re:Linear Algebra: What matrices are by Retra on Saturday August 29, 2015 @10:09AM (#10140029)
It's basically duck-typing. If you can do arithmetic on it, it's a number. If you can do matrix operations, it's a matrix. If it satisfies the axioms of X, it's an X.
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Re:Linear Algebra: What matrices are by AstralStorm on Saturday August 29, 2015 @11:39AM (#10140338)
Not true. You can do arithmetic on many things that are not a number. This is why objects such as "rings" exist.

Matrix is not defined just by operations like a ring is, but also by structure - you have N independent axes in a specified space.

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Re:Linear Algebra: What matrices are by verbin217 on Saturday August 29, 2015 @12:39PM (#10140549)
That's a bit pedantic but sure. Here it is fixed:

> If you can do numeric arithmetic on it, it's a number.

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Re:Linear Algebra: What matrices are by tomadi on Saturday August 29, 2015 @09:53PM (#10142006)
That is begging the question. What does "numeric" mean?
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Re:Linear Algebra: What matrices are by Retra on Saturday August 29, 2015 @06:48PM (#10141616)
Do you have a definition of number that addresses this?

>you have N independent axes in a specified space.

Only if you have an operation that maps the matrices to that space.

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