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Repeated numbers in Matrix
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John
Feb 21, 2012, 1:37:12 PM2/21/12
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Hi,
I'm working on a problem where I need to get a+b+c=0
With the M = Matrix
for i = 1:(length(M)-2
a= M(i)
for j = i+1:(length(M)-1
b= M(j)
for k = j+1:(length(M))
c= M(k)
if a+b+c==0
x(i,:) = [a b c]
What I need is to have it from not popping out repeated numbers in each of the rows
for example, 2 -2 0 is the same as -2 2 0.
what would be a good way to get it to not do this?
I'm working on a problem where I need to get a+b+c=0
With the M = Matrix
for i = 1:(length(M)-2
a= M(i)
for j = i+1:(length(M)-1
b= M(j)
for k = j+1:(length(M))
c= M(k)
if a+b+c==0
x(i,:) = [a b c]
What I need is to have it from not popping out repeated numbers in each of the rows
for example, 2 -2 0 is the same as -2 2 0.
what would be a good way to get it to not do this?
Matt J
Feb 21, 2012, 1:51:11 PM2/21/12
to
"John " <drkan...@yahoo.com> wrote in message <ji0o8n$76b$1...@newscl01ah.mathworks.com>...
Are these triples equivalent because order is not important, or because sign is not important? If the former
unique(sort(x,2),'rows');
> Hi,
>
> I'm working on a problem where I need to get a+b+c=0
>
> With the M = Matrix
> for i = 1:(length(M)-2
> a= M(i)
> for j = i+1:(length(M)-1
> b= M(j)
> for k = j+1:(length(M))
> c= M(k)
> if a+b+c==0
> x(i,:) = [a b c]
>
>
> What I need is to have it from not popping out repeated numbers in each of the rows
> for example, 2 -2 0 is the same as -2 2 0.
===============
>
> I'm working on a problem where I need to get a+b+c=0
>
> With the M = Matrix
> for i = 1:(length(M)-2
> a= M(i)
> for j = i+1:(length(M)-1
> b= M(j)
> for k = j+1:(length(M))
> c= M(k)
> if a+b+c==0
> x(i,:) = [a b c]
>
>
> What I need is to have it from not popping out repeated numbers in each of the rows
> for example, 2 -2 0 is the same as -2 2 0.
Are these triples equivalent because order is not important, or because sign is not important? If the former
unique(sort(x,2),'rows');
John
Feb 21, 2012, 2:10:14 PM2/21/12
to
> Are these triples equivalent because order is not important, or because sign is not important? If the former
>
> unique(sort(x,2),'rows');
Also forgot to say, but the matrix M pops out different values every time because it uses "randi", so the results for the x(i,:) are can sometimes have repeats and sometimes not have any repeats.
Does this affect the use of unique(sort(x,2),'rows'); ?
John
Feb 21, 2012, 2:27:11 PM2/21/12
to
Tried putting in unique(sort(x,2),'rows');
It only seems to sort the numbers
Ex for one of the one's I tried
2 2 -4
3 -4 1
-3 2 1 %
-3 2 1 %
% are repeats which I'm trying to get rid of
It only seems to sort the numbers
Ex for one of the one's I tried
2 2 -4
3 -4 1
-3 2 1 %
-3 2 1 %
% are repeats which I'm trying to get rid of
Matt J
Feb 21, 2012, 2:59:11 PM2/21/12
to
"John " <drkan...@yahoo.com> wrote in message <ji0r6f$hdf$1...@newscl01ah.mathworks.com>...
================
Not sure what the problem is, but I'm guessing there is code you're not showing. When I plug in the data you have above, the duplicates are gone, as expected:
>> unique(sort(x,2),'rows')
ans =
-4 1 3
-4 2 2
-3 1 2
Not sure what the problem is, but I'm guessing there is code you're not showing. When I plug in the data you have above, the duplicates are gone, as expected:
>> unique(sort(x,2),'rows')
ans =
-4 1 3
-4 2 2
-3 1 2
John
Feb 21, 2012, 5:46:11 PM2/21/12
to
I'm trying to eliminate numerically equivalent values so that it doesn't have any repeated solutions.
This should be able to match solutions which contain the same values but in different orders.
Ex.
[3 1 -4] and [3 -4 1] are solutions, but the method should still identify them as equivalent and only give one of them.
This should be able to match solutions which contain the same values but in different orders.
Ex.
[3 1 -4] and [3 -4 1] are solutions, but the method should still identify them as equivalent and only give one of them.
Matt J
Feb 21, 2012, 6:23:09 PM2/21/12
to
"John " <drkan...@yahoo.com> wrote in message <ji16ri$sd1$1...@newscl01ah.mathworks.com>...
=================
Once again, though, I think the code I gave you does that. It worked for me on the sample data set that you gave.
Once again, though, I think the code I gave you does that. It worked for me on the sample data set that you gave.
John
Feb 21, 2012, 7:10:11 PM2/21/12
to
It works for some of the values of M, but I need it to work for every one of them
For the random values M = 5 0 -4 4 2 -1 5 -2
I get
5 -4 -1 %
0 2 -2
-4 -1 5 %
% these 2 are repeated
Ex.
M = 2 -1 -3 -4 0 -3 3 -1
ans =
2 -1 -1
0 0 0 %
-3 0 3 %
0 0 0 %
0 -3 3 %
%Other repeats
For the random values M = 5 0 -4 4 2 -1 5 -2
I get
5 -4 -1 %
0 2 -2
-4 -1 5 %
% these 2 are repeated
Ex.
M = 2 -1 -3 -4 0 -3 3 -1
ans =
2 -1 -1
0 0 0 %
-3 0 3 %
0 0 0 %
0 -3 3 %
%Other repeats
Matt J
Feb 22, 2012, 11:12:13 AM2/22/12
to
"John " <drkan...@yahoo.com> wrote in message <ji1bp3$dfu$1...@newscl01ah.mathworks.com>...
======================
Please execute ONLY the following 2 consecutive lines and tell me what the output is,
x=[ 5 -4 -1
0 2 -2
-4 -1 5] ;
Output=unique(sort(x,2),'rows')
Please execute ONLY the following 2 consecutive lines and tell me what the output is,
x=[ 5 -4 -1
0 2 -2
-4 -1 5] ;
Output=unique(sort(x,2),'rows')
John
Feb 22, 2012, 11:59:14 AM2/22/12
to
Oh wow now I feel stupid been trying to define a new variable instead of use the same output value for it.
Now I just need it to show x=0 when the matrix has no values
Now I just need it to show x=0 when the matrix has no values
John
Feb 22, 2012, 12:04:13 PM2/22/12
to
the x =0 might be also why I'm getting and error for some of the random numbers
Undefined function or variable "x".
Error in test (line 24)
x = unique(sort(x,2),'rows');
Undefined function or variable "x".
Error in test (line 24)
x = unique(sort(x,2),'rows');
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