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Re: sorting, ranking
Posted:
Aug 21, 2009 3:53 PM


"Wyatt " <hello@hello.com> wrote in message news:h6moqe$sqf$1@fred.mathworks.com... > that did the trick steve. It just seems to me that > > rank = temp(I) > > should be valid syntax,
It is. It just doesn't do what you expect it to do.
> and is more intuitive than writing > > rank(I) = temp
Why do you say that? "rank = temp(I)" is a valid MATLAB command in this scenario, but so is "rank = I.^2" or "rank = sin(cos(tan(I)))". Each of those commands do something different; for the application you described in your original post, the command that does what you want is "rank(I) = temp".
Although you probably shouldn't use rank as a variable name, unless you're okay with not being able to use the RANK function in the same piece of code.
> perhaps because I'm thinking that if I wanted to arbitrarily pull out > values [7 4 9 1] from a vector A I would write > > A([7 4 9 1]) > > and it would give me the 7th 4th 9th and 1st values from A in that order.
Yes. And if you wanted to store 1:4 into the 7th, 4th, 9th, and 1st elements of A, you'd use:
A([7 4 9 1]) = (1:4);
Just because one command works does not necessarily rule out a modification of that command also working and doing something slightly different.
 Steve Lord slord@mathworks.com



