Subtracting in matrix, column to column (Basic MatLab)?

2 次查看（过去 30 天）

John wick 2019-8-11

评论： John wick 2019-8-11

Given a 45×48 matrix, type a single command that subtracts column 36 from column 44

i answered this but it pops up as Error: Invalid use of operator. Is there something wrong or should it be in different type of form.

(:,36)-(:,44)

Star Strider 2019-8-11

Your idea is essentially correct. I have no idea what the question wants.

Perhaps providing a matrix and a reference to it will work:

A = rand(45,48);
col_dif = A(:,36)-A(:,44)

John wick 2019-8-11

Ohhh Thank you very much for helping and explaining it. Love ya!

Star Strider 2019-8-11

As always, my pleasure!

Image Analyst 2019-8-11

编辑：Image Analyst 2019-8-11

You need to put the matrix name in there, and a result variables, like

result = m(:,44) - .....................

etc.

Image Analyst 2019-8-11

Well you can't just have indexes within parentheses like (:,44), because how could MATLAB possibly know which matrix you're referring to.

John wick 2019-8-11

I guess i just got the idea on how it works but not really master it. Thank you for helping me out!

MATLAB Language Fundamentals Matrices and Arrays Matrix Indexing

在 Help Center 和 File Exchange 中查找有关 Matrix Indexing 的更多信息

Find the treasures in MATLAB Central and discover how the community can help you!

Translated by