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Topic: Extracting particular row of a matrix based on specific condition
Replies: 14   Last Post: Jan 3, 2014 10:03 AM

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 dpb Posts: 9,850 Registered: 6/7/07
Re: Extracting particular row of a matrix based on specific condition
Posted: Dec 30, 2013 9:30 AM

On 12/29/2013 3:25 PM, Poulomi wrote:

...Don't toppost -- hard conversation follow makes...

> dpb <none@non.net> wrote in message <l9q2j3\$pa8\$1@speranza.aioe.org>...
>> On 12/29/2013 2:39 PM, Poulomi wrote:
>> > "Poulomi" wrote in message <l9q0oj\$7ef\$1@newscl01ah.mathworks.com>...
>> ...
>> >> ...A = [519 520 521 1000]
>> ...
>> >> B = [1000 0.12 0.005 0.1
>> >> 520 0.13 0.001 0.89
>> >> 518 0.12 0.002 0.98
>> >> 600 0.14 0.004 0.90];
>> >>
>> >> I need to pick up the values in A matrix, find out common 1st column
>> >> element in Matrix B and extract corresponding row. Say, 520, 1000 is
>> >> common in both matrix, so my output will be a new matrix C = [0.12
>> >> 0.005 0.1
>> >> 0.13 0.001 0.89];
>> >>
>> >> Let me know how to do so. Thanks,

>> >
>> > Sorry my output C will be in same order as the elements in A matrix, so
>> > C = [0.13 0.001 0.89
>> > 0.12 0.005 0.1]. Please let me know. Thanks,

>>
>> C=B(ismember(B(:,1),A'),2:end);

> Thanks, but I need the order to be maintained same as A matrix, so that
> C = [0.13 0.001 0.89
> 0.12 0.005 0.1].

In that is mandatory either reorder or use accumarray() or a loop to
process in that order.

--

Date Subject Author
12/29/13 Pg
12/29/13 Pg
12/29/13 dpb
12/29/13 Pg
12/30/13 dpb
12/31/13 Bruno Luong
12/31/13 dpb
1/1/14 Bruno Luong
1/2/14 dpb
1/2/14 Pg
1/2/14 dpb
1/3/14 dpb
1/2/14 Bruno Luong
1/2/14 dpb
1/3/14 dpb