Thread Subject: codes for loops required...

let ....
A=[2 ;5 ;8 ;10 ;15]
B=[3 ;4 ;5 ;13 ;20]
now compare each element of matrix A with each element of matrix B
if the difference between the element of A and B is not >= 2 then discard it from A. or if the difference is >= 2 take the element of matrix A into another matrix C.

 the procces will be like this...........
abs(2-3)=1 ,not>=2 so dont take 2 from A
then
abs(5-3)=2, (>=2)
but abs(5-4)=1 ,not >=2 so dont take 5 also
then
abs(8-3)=5 .ok
abs(8-4)=4 .ok
abs (8-5)=3 .ok
abs(8-13)=5 ok
abs(8-20)=12 ok ... so now take 8 from matrix A.

finally for the given matrix A and B
C = [8 ;10; 15]

plz help me with the loop code.....

"Fuad Ahsan" <itsfuad01@hotmail.com> wrote in message <gfs28m$ng4$1@fred.mathworks.com>...
> let ....
> A=[2 ;5 ;8 ;10 ;15]
> B=[3 ;4 ;5 ;13 ;20]
> now compare each element of matrix A with each element of matrix B
> if the difference between the element of A and B is not >= 2 then discard it from A. or if the difference is >= 2 take the element of matrix A into another matrix C.
>
> the procces will be like this...........
> abs(2-3)=1 ,not>=2 so dont take 2 from A
> then
> abs(5-3)=2, (>=2)
> but abs(5-4)=1 ,not >=2 so dont take 5 also
> then
> abs(8-3)=5 .ok
> abs(8-4)=4 .ok
> abs (8-5)=3 .ok
> abs(8-13)=5 ok
> abs(8-20)=12 ok ... so now take 8 from matrix A.
>
> finally for the given matrix A and B
> C = [8 ;10; 15]
>
> plz help me with the loop code.....

This is pretty obvious homework because you would never use a loop. Could at least post what you tried if you're stuck.

C = A(abs(A-B)>2);

~Adam

"Fuad Ahsan" <itsfuad01@hotmail.com> wrote in message <gfs28m$ng4$1@fred.mathworks.com>...
> let ....
> A=[2 ;5 ;8 ;10 ;15]
> B=[3 ;4 ;5 ;13 ;20]
> now compare each element of matrix A with each element of matrix B
> if the difference between the element of A and B is not >= 2 then discard it from A. or if the difference is >= 2 take the element of matrix A into another matrix C.
>
> the procces will be like this...........
> abs(2-3)=1 ,not>=2 so dont take 2 from A
> then
> abs(5-3)=2, (>=2)
> but abs(5-4)=1 ,not >=2 so dont take 5 also
> then
> abs(8-3)=5 .ok
> abs(8-4)=4 .ok
> abs (8-5)=3 .ok
> abs(8-13)=5 ok
> abs(8-20)=12 ok ... so now take 8 from matrix A.
>
> finally for the given matrix A and B
> C = [8 ;10; 15]
>
> plz help me with the loop code.....

% This should get you started...

for nB = 1:length(B)
   for nA = 1:length(A)
      if abs(A(nA) - B(nB)) >= 2
         % your turn, put your code here
      end
   end
end

> This is pretty obvious homework because you would never use a loop. Could at least post what you tried if you're stuck.
>
> C = A(abs(A-B)>2);
>
> ~Adam


///////////////////////////////////////////////

c1 = sort (randint (70,1,[200,800]))
c2 = sort (randint (70,1,[200,800]))

A1 = abs (c1-c2)
d_1 = find (A1>=2)
d1 = c1(d_1)
///////////////////////////////////////////////
 I did this code, but the problem is that it just compare the elements in same position of matrix c1 and c2.
but what i need is that compare each element of c1 with each element of c2. then if the difference is >=2 for all elements of c2 then take that element of c1.

now can u tell me how can i do this .
by the way its not a homework, i am trying to develop a code for channel assignment problem which i will use in Genetic algorithm (MOEA),

"Fuad Ahsan" <itsfuad01@hotmail.com> wrote in message <gfu382$kdg$1@fred.mathworks.com>...
> > This is pretty obvious homework because you would never use a loop. Could at least post what you tried if you're stuck.
> >
> > C = A(abs(A-B)>2);
> >
> > ~Adam
>
>
> ///////////////////////////////////////////////
>
> c1 = sort (randint (70,1,[200,800]))
> c2 = sort (randint (70,1,[200,800]))
>
> A1 = abs (c1-c2)
> d_1 = find (A1>=2)
> d1 = c1(d_1)
> ///////////////////////////////////////////////
> I did this code, but the problem is that it just compare the elements in same position of matrix c1 and c2.
> but what i need is that compare each element of c1 with each element of c2. then if the difference is >=2 for all elements of c2 then take that element of c1.
>
> now can u tell me how can i do this .
> by the way its not a homework, i am trying to develop a code for channel assignment problem which i will use in Genetic algorithm (MOEA),

Much better. :-)

c1 = floor(601*rand(70,1))+200;
c2 = floor(601*rand(70,1))+200;

mid = bsxfun(@minus, c1, c2');
d1 = all(abs(mid)>=2);

----

note: you could combine the last two lines, I just separated for clarity
d1 = all(abs(bsxfun(@minus, c1, c2'))>=2);

~Adam

> Much better. :-)
>
> c1 = floor(601*rand(70,1))+200;
> c2 = floor(601*rand(70,1))+200;
>
> mid = bsxfun(@minus, c1, c2');
> d1 = all(abs(mid)>=2);
>
> ----
>
> note: you could combine the last two lines, I just separated for clarity
> d1 = all(abs(bsxfun(@minus, c1, c2'))>=2);
>
> ~Adam


what the syntex "bsxfun" doing here?
i could not run it :-(

"Fuad Ahsan" <itsfuad01@hotmail.com> wrote in message <gfuvup$5n7$1@fred.mathworks.com>...
> > Much better. :-)
> >
> > c1 = floor(601*rand(70,1))+200;
> > c2 = floor(601*rand(70,1))+200;
> >
> > mid = bsxfun(@minus, c1, c2');
> > d1 = all(abs(mid)>=2);
> >
> > ----
> >
> > note: you could combine the last two lines, I just separated for clarity
> > d1 = all(abs(bsxfun(@minus, c1, c2'))>=2);
> >
> > ~Adam
>
>
> what the syntex "bsxfun" doing here?
> i could not run it :-(

If you can't run it then your version of MATLAB is too old. You can download a replacement for bsxfun on the file exchange.

"Fuad Ahsan" <itsfuad01@hotmail.com> wrote in message <gfuvup$5n7$1@fred.mathworks.com>...

> > note: you could combine the last two lines, I just separated for clarity
> > d1 = all(abs(bsxfun(@minus, c1, c2'))>=2);
> >
> > ~Adam
>
>
> what the syntex "bsxfun" doing here?
> i could not run it :-(

Because you have an old matlab release.

John

"matt dash" <n.a@mail.com> wrote in message <gfv0um$i2k$1@fred.mathworks.com>...
> "Fuad Ahsan" <itsfuad01@hotmail.com> wrote in message <gfuvup$5n7$1@fred.mathworks.com>...
> > > Much better. :-)
> > >
> > > c1 = floor(601*rand(70,1))+200;
> > > c2 = floor(601*rand(70,1))+200;
> > >
> > > mid = bsxfun(@minus, c1, c2');
> > > d1 = all(abs(mid)>=2);
> > >
> > > ----
> > >
> > > note: you could combine the last two lines, I just separated for clarity
> > > d1 = all(abs(bsxfun(@minus, c1, c2'))>=2);
> > >
> > > ~Adam
> >
> >
> > what the syntex "bsxfun" doing here?
> > i could not run it :-(
>
> If you can't run it then your version of MATLAB is too old. You can download a replacement for bsxfun on the file exchange.
>
 
or, as an alternative (aka the "old" way):
[C1 C2] = meshgrid(c1, c2);
d1 = all(abs(C1-C2) >= 2);

~Adam

> >
> > If you can't run it then your version of MATLAB is too old. You can download a replacement for bsxfun on the file exchange.
> >
>
> or, as an alternative (aka the "old" way):
> [C1 C2] = meshgrid(c1, c2);
> d1 = all(abs(C1-C2) >= 2);
>
> ~Adam


thanks

here d1 is a 1x70 matrix and if satisfy the condition (>= 2) fill the position by 1 otherwise 0.
but now how to find out the the element oc c1 whice satisfied the condition.
note: c1 is 70x1 matrix.
i mean i want to take only elements that are >=2 from elements of c2.
can you plz help me on this...........

"Fuad Ahsan" <itsfuad01@hotmail.com> wrote in message <gfvbv5$aul$1@fred.mathworks.com>...
> > >
> > > If you can't run it then your version of MATLAB is too old. You can download a replacement for bsxfun on the file exchange.
> > >
> >
> > or, as an alternative (aka the "old" way):
> > [C1 C2] = meshgrid(c1, c2);
> > d1 = all(abs(C1-C2) >= 2);
> >
> > ~Adam
>
>
> thanks
>
> here d1 is a 1x70 matrix and if satisfy the condition (>= 2) fill the position by 1 otherwise 0.
> but now how to find out the the element oc c1 whice satisfied the condition.
> note: c1 is 70x1 matrix.
> i mean i want to take only elements that are >=2 from elements of c2.
> can you plz help me on this...........

>> c1 = floor(601*rand(70,1))+200;
>> c2 = floor(601*rand(70,1))+200;
>> [C1 C2] = meshgrid(c1, c2);
>> d_1 = all(abs(C1-C2) >= 2);
>> d1 = c1(find(d_1))'

~Adam

"Adam" <not.real@email.com> wrote in message <gfvf0n$le6$1@fred.mathworks.com>...
>
> >> c1 = floor(601*rand(70,1))+200;
> >> c2 = floor(601*rand(70,1))+200;
> >> [C1 C2] = meshgrid(c1, c2);
> >> d_1 = all(abs(C1-C2) >= 2);
> >> d1 = c1(find(d_1))'
>
> ~Adam

thanks Adam
this function works perfectly , but i cann't use it several times in one cade , after some stage the memory cann't hold the values :-(
and show some errors.
btw i have the bsxfun function (downloaded from file ex.) but it also shows errors in associated file bsxarg.m

"Fuad Ahsan" <itsfuad01@hotmail.com> wrote in message <gg1itq$4pg$1@fred.mathworks.com>...
> "Adam" <not.real@email.com> wrote in message <gfvf0n$le6$1@fred.mathworks.com>...
> >
> > >> c1 = floor(601*rand(70,1))+200;
> > >> c2 = floor(601*rand(70,1))+200;
> > >> [C1 C2] = meshgrid(c1, c2);
> > >> d_1 = all(abs(C1-C2) >= 2);
> > >> d1 = c1(find(d_1))'
> >
> > ~Adam
>
> thanks Adam
> this function works perfectly , but i cann't use it several times in one cade , after some stage the memory cann't hold the values :-(
> and show some errors.
> btw i have the bsxfun function (downloaded from file ex.) but it also shows errors in associated file bsxarg.m

Did you look at what the individual steps are doing?

You're going to need to either re-use, or clear variables.

~Adam