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Topic: doubts in matlab
Replies: 3   Last Post: Feb 18, 2013 12:00 AM

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dpb

Posts: 8,217
Registered: 6/7/07
Re: doubts in matlab
Posted: Feb 18, 2013 12:00 AM
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On 2/17/2013 9:57 PM, Shobana wrote:
> dpb <none@non.net> wrote in message <kfqpf8$mhc$1@speranza.aioe.org>...
>> On 2/17/2013 5:21 AM, Shobana wrote:
>> > Hai...
>> > I am tried to find minimum value of particular columns and rows
>> > separately but i am getting wrong answers.
>> > for example a = [1 2 3 ;
>> > 6 5 4;
>> > 8 1 7]
>> > [x y] = min(a(2:end,2))
>> >
>> > instead of getting x= 3 y =2 i am getting some other value.how to write
>> > correct code for this concept.
>> > Thanks in advance

>>
>> a(2:end,2) ==> [5;1] % 2nd to last rows, 2nd column
>>
>> so you should find [x,y] == [1,2]
>>
>> Not sure which you were really after that would return your expected
>> results otomh I don't see one.
>> sorry its not working.its showing me an error


Well, w/o seeing what you did and the error, can't comment...the above
is commentary, not code. The subset of a given by (2:end,2) is a column
vector containing 5,1. So, the min() of that vector is 1 and the second
location.

>> If you're trying to write a subset of the array and then work min() on
>> the 2nd dimension, the ',2' is misplaced above (and you're missing the
>> 2nd dimension for the subscript expression if you simply move it.
>>
>> Try something like
>>
>> [x ix] = min(a(2:end,:),2)

...

Oh, sorry...for the dimension optional argument, need an empty
comparison field--the above compares the subarray to the constant 2, not
what I was intending...

[x ix] = min(a(2:end,:),[],2);

doc min

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