error in selecting data

FIR
2011 11 15
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i have a data of 2 columns
d= [12] 'A'
[23] 'B'
[18] 'H'
d1=[23 45]
out = [d1, d(ismember(d(:,1),d1(:,1),'rows'),1:end)]
if i do this i get error
Input must be cell arrays of strings
please help

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Sven
Sven 2011-11-15

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Hi FIR,
The error comes because the ismember() function expects either a matrix of numbers or a cell array of strings. Since d is a cell, you provided a cell array of numbers which is unfortunately invalid. Try converting to numbers like the following:
dMask = ismember(cell2mat(d(:,1)), d1);
Secondly, you were trying to concat d1 (which is a 1x2 matrix) with various rows of a cell (ie, an nx2 cell):
out = [d1, d(dMask,:)]
This won't work on two counts:
1. Cells won't concat with matrices - one of them needs to be converted.
2. d1 is 1x2, which won't concat if your result has more than 1 rows.
------
So, I've updated my answer as below from the comments you made. Firstly, we have your inputs d and d1 as follows:
d = {12 'A'; 23 'B'; 18 'H'; 12 'P'};
d1 = [23 45;18 10];
And what you actually want to do is concat d1 with its corresponding indices into d. Note that this means you're asking which entries in the first column of d1 are members of the first column of d... Note that this is the opposite ordering from your original question, but it seems more logical. Try the following two lines, I think that they answer your question:
[dMask, indices] = ismember(d1(:,1), cell2mat(d(:,1)));
[num2cell(d1(dMask,:)) d(indices,2)];
Does this help?

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FIR
FIR 2011-11-16
sven please suggest .assuming that d1 has more rows
for example d has 4000 rows and 62 column,d has 10 rows
FIR
FIR 2011-11-16
Sven i get an error wen executing ur command
Error using ==> cell2mat
Too many input arguments.
Error in ==> qq at 8
dMask = ismember(cell2mat(d(:,1), d1));
Sven
Sven 2011-11-16
So answer this:
A = [1 2];
B = [10 20; 15 40];
Here "A" has 1 row, "B" has 2 rows. Please clarify what your final answer would look like if you combined A and B.
Sven
Sven 2011-11-16
Oh, sorry, there was a typo: I missed a ")". It's fixed now
FIR
FIR 2011-11-16
but sven ur A and B data is wrong
from my dat d and d1
i need output as
23 45 B
if
data is
d= [12] 'A'
[23] 'B'
[18] 'H'
[12] 'P'
d1=[23 45;18 10]
but sven ur A and B data is wrong
from my dat d and d1
i need output as
23 45 B
if
data is
d= [12] 'A'
[23] 'B'
[18] 'H'
[12] 'P'
d1=[23 45;18 10]
i NEED OUTPUT AS
23 45 B
18 10 H
Sven
Sven 2011-11-16
Answer updated. What do you think?
FIR
FIR 2011-11-16
THANKS A LOT Sven,this is what i was expecting
FIR
FIR 2011-11-16
Another one question I have 4000 rows and 5 columns I have to divide this data into 5 groups so that i will have 800 rows and 25 columns,plz help
Sven
Sven 2011-11-16
If the question's answered, hit accept :)
Does the following do what you wanted?
MAT_4000by5 = rand(4000,5);
MAT_800by25 = reshape(MAT_4000by5,800,25);
FIR
FIR 2011-11-16
Thanks Sven i have 2 more questions ,
I have 5 columns and 800 rows and the last row contains percentage ranging from (90.20 to 99.98),first i want to round off that percentage ans have to display it withs all its column and ten i want to select two percentage which is highest and want to dispaly with all its 5 columns
output must be
1 3 1 0 99
2 3 1 0 98
next i want to find five fold crodd validation error for the third column,by using in built function,please help
Sven
Sven 2011-11-16
I'm a bit lost on what you want to do here, and it seems quite a different topic to the original question. I suggest hitting "accept" to the original question, and then asking a new question specifically about "how to format rows columns for display". If you can make a short example showing exactly the input you have and the output you want, I'm sure it will get a clear answer.
FIR
FIR 2011-11-16
Sven u have not answered to my question

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