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Topic: Creating Booleans from Vectors
Replies: 5   Last Post: Sep 17, 2013 11:23 PM

 Messages: [ Previous | Next ]
 dpb Posts: 9,850 Registered: 6/7/07
Re: Creating Booleans from Vectors
Posted: Sep 17, 2013 7:46 PM

On 9/17/2013 6:25 PM, Roger Stafford wrote:
> "Michael " <mabowles@syr.edu> wrote in message
> <l1aehk\$d3o\$1@newscl01ah.mathworks.com>...

>> x = [1 3 8 10 11];
>> y = [2 6 9 15]; xy_ordered = [1 2 3 6 8 9 10 11 15];
>>
>> cX = [1 0 1 0 1 0 1 1 0]
>> cY = [0 1 0 1 0 1 0 0 1]; %by definition the is ~cX..

> - - - - - - - - - -
> cX = ismember(xy_ordered,x);
> cY = ismember(xy_ordered,y);
>
> The vectors cX and cY are logical vectors which contain true's and
> false's. To transform them to 1's and 0's, apply "double" to them. Note
> that if a number lies in both x and y, there will be a 1 (true) in both
> cX and cY in the same position. It is not necessary that x, y, or
> xy_ordered be ordered for this code to operate.

Good catch -- I was trying to figure out the indices labeled just X|Y
from x and y instead of the combined...

And, of course,

cY = ~cX;

or vice versa, if use ismember on the other first...

--

Date Subject Author
9/17/13 Michael
9/17/13 dpb
9/17/13 Roger Stafford
9/17/13 dpb
9/17/13 Michael
9/17/13 Michael