I think this is a documentation error

If I search the help for "array vs matrix", the 7th and 8th entries are rdivide and ldivide. I don't see a Quote button, so I'll post what I see there in a code block:

rdivide, ./ - Right array division
This MATLAB function divides each element of A by the corresponding element of B.
Documentation > MATLAB > Language Fundamentals > Operators and Elementary Operations > Arithmetic Operations

ldivide, .\ - Left array division
This MATLAB function divides each element of A by the corresponding element of B.
Documentation > MATLAB > Language Fundamentals > Operators and Elementary Operations > Arithmetic Operations

It seems to me that the secobd line under ldivide should be:

This MATLAB function divides each element of B by the corresponding element of A.

No? Shouldn't the A and B be reversed?

[per isakson]

Yes, it looks so, but in the description of ldivide the positions of A and B are switched. "x = B.\A divides each element of A by the corresponding element of B." Seems as if the search function replaces the formula by "This function". First of April was a week ago:)

Answer 1

[Walter Roberson]

No, ldivide says

B.\A divides each element of A by the corresponding element of B

whereas ldivide says

A./B divides each element of A by the corresponding element of B.

Notice that the order of A and B are reversed between the two of them.

>> [3 5].\[2 4]
ans =
         0.666666666666667                       0.8

And we see that the 2 from A (the second operand) was indeed divided by the 3 from B (the first operand)

[Cynthia Moore]

OK. The text in the search list is in agreement with the text in the separate function descriptions. Good. But, for me, the text is unneccessarily misleading. I suggest that the text in the search list should read:

rdivide, ./ - Right array division
A./B divides each element of A by the corresponding element of B.
Documentation > MATLAB > Language Fundamentals > Operators and Elementary Operations > Arithmetic Operations

ldivide, .\ - Left array division
A.\B divides each element of B by the corresponding element of A.
Documentation > MATLAB > Language Fundamentals > Operators and Elementary Operations > Arithmetic Operations

For most people, that would be enough of a description that they would not even need to read the full text. But if they did, both writeups should always have A as the first array and B as the second array (IMHO).