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From: someone on 19 Jul 2010 15:07
"Heman " <kokahemant(a)hotmail.com> wrote in message <i226bp$fuc$1(a)fred.mathworks.com>...
> "someone" <someone(a)somewhere.net> wrote in message <i225ai$afo$1(a)fred.mathworks.com>...
> > "Heman " <kokahemant(a)hotmail.com> wrote in message <i223ab$2d6$1(a)fred.mathworks.com>...
> > > Hi all,
> > >
> > > I am trying to run this matlab code but am facing with a few errors. Can some one help me out?
> > > I ran this code with a random input signal and it was working. Now i tried running with the input file which has 1024 hexadecimal values.
> > >
snip ...

> > It would help us if you said what the errror messages were a least.
>
> I cannot put the input file as its 1024 hexadecimal data. so its a very big file. I dont know if there is an option of attaching the files here. The eror messages:
>
> ??? Error using ==> horzcat
> CAT arguments dimensions are not consistent.
>
> Error in ==> lms_prof at 36
> x1=[x(n:-1:1)' zeros(1,ntaps-n)];
> **********
> I then changed the statement to
> x1=[x(n:-1:1) zeros(1,ntaps-n)];
> ********

OK, that was a good try. It depends on what you want x1 to be, a row vector, a column vector, or a matrix. Other possibilities are:

> x1=[x(n:-1:1)'; zeros(ntaps-n,1)];
> x1=[x(n:-1:1); zeros(1,ntaps-n)];

Are n:-1:1 and 1:(ntaps-n) the same length?
Or are you just "zero padding" your vector?

> The next error :
> ??? Error using ==> mtimes
> Inner matrix dimensions must agree.
>
> Error in ==> lms_prof at 41
> y(n)=x1*h';
> *****************
> The dimentions of h and x1 are 1x64. I changed the statement to y(n)=x1'*h;
> But still same error.

The above are matrix multiplies, by default, in MATLAB. If you simply want element-by-element mutiplies, then change:
> y(n)=x1*h';
to
> y(n)=x1.*h'; % y(n)=x1.*h; would give the same answer as well

You may other such problems further down in your code (i.e., change / to ./ etc.).
Since it looks like y is a vector, I assume that element-by-element is what you want.
But, it is up to you to decide.

>
> I you want the data file then just let me know i can send an email or if i can attach here then please tell me. I am new to this forum.
>
> Thank you
From: Heman on 19 Jul 2010 15:38
> > ??? Error using ==> horzcat
> > CAT arguments dimensions are not consistent.
> >
> > Error in ==> lms_prof at 36
> > x1=[x(n:-1:1)' zeros(1,ntaps-n)];
> > **********
> > I then changed the statement to
> > x1=[x(n:-1:1) zeros(1,ntaps-n)];
> > ********
>
> OK, that was a good try. It depends on what you want x1 to be, a row vector, a column vector, or a matrix. Other possibilities are:
>
> > x1=[x(n:-1:1)'; zeros(ntaps-n,1)];
> > x1=[x(n:-1:1); zeros(1,ntaps-n)];

Neither one works. It gives me error. the only option which i tried earlier works here.

>
> Are n:-1:1 and 1:(ntaps-n) the same length?
> Or are you just "zero padding" your vector?

yes, i am padding zeros.

>
> > The next error :
> > ??? Error using ==> mtimes
> > Inner matrix dimensions must agree.
> >
> > Error in ==> lms_prof at 41
> > y(n)=x1*h';
> > *****************
> > The dimentions of h and x1 are 1x64. I changed the statement to y(n)=x1'*h;
> > But still same error.
>
> The above are matrix multiplies, by default, in MATLAB. If you simply want element-by-element mutiplies, then change:
> > y(n)=x1*h';
> to
> > y(n)=x1.*h'; % y(n)=x1.*h; would give the same answer as well
>
I tried these options. still the following erorrs:
??? In an assignment A(I) = B, the number of elements in B and
I must be the same.

Error in ==> lms_prof at 41
y(n)=x1.*h;
*******
??? Error using ==> times
Matrix dimensions must agree.

Error in ==> lms_prof at 41
y(n)=x1.*h';

> You may other such problems further down in your code (i.e., change / to ./ etc.).
> Since it looks like y is a vector, I assume that element-by-element is what you want.
> But, it is up to you to decide.
From: Andy on 19 Jul 2010 15:52
I think the error message is very clear: x1 and h are not the size you think they are. Type:

dbstop if error

Then run your code. When it errors, type:

size(x1)
size(h)

and post the result here.
From: Heman on 19 Jul 2010 16:14
"Andy " <myfakeemailaddress(a)gmail.com> wrote in message <i22ad5$787$1(a)fred.mathworks.com>...
> I think the error message is very clear: x1 and h are not the size you think they are. Type:
>
> dbstop if error
>
> Then run your code. When it errors, type:
>
> size(x1)
> size(h)
>
> and post the result here.

I did as you said here are the display results:

??? Error using ==> times
Matrix dimensions must agree.

Error in ==> lms_prof at 45
y(n)=x1.*h';

K>> size(h)

ans =

1 64

K>> size(x1)

ans =

1 64
From: Andy on 19 Jul 2010 16:23
Well there is your problem. If h is 1x64, then h' is 64x1. When using the .* element-by-element multiplication, both arrays need to be the same size. So you cannot use .* to multiply the elements of a 1x64 array with the elements of a 64x1 array.
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