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Topic: interpolate
Replies: 14   Last Post: Apr 9, 2015 1:34 PM

 Messages: [ Previous | Next ]
 maryam Posts: 17 Registered: 12/25/12
Re: interpolate
Posted: Dec 26, 2012 8:45 PM

dpb <none@non.net> wrote in message <kbg5ol\$ugl\$1@speranza.aioe.org>...
> On 12/26/2012 5:03 PM, maryam wrote:
> > dpb <none@non.net> wrote in message <kbfhar\$1lo\$1@speranza.aioe.org>...
> >> On 12/26/2012 12:29 PM, maryam wrote:
> >> ...

> >> > how could I interpolate rows of a matrix so that original value of rows
> >> > don't change?

> >>
> >> Didn't we do this before the holidays?????
> >>
> >> doc interp1
> >>

> >> >> X = 0:10; V = sin(X); Xq = 0:.25:10;
> >> >> Vq = interp1(X,V,Xq);
> >> >> all(Vq(Xq==fix(Xq))==V)

> >> ans =
> >> 1

> >> >>
> >>
> >>
> >> What else do you need????

> > ---------------------------------------------------
> > I searched but I didn't find it
> > thank you very much for your answer but I mean we have a matrix n-by-m:
> > assume M= [a b c;d e f; g h i]
> > I want to interpolate its rows so that is equal to
> > M=[a a+d a+2d a+3d ... 7d b b+d ... b+7d c... c+7d ; d... d+7d... f+7d ;
> > g ... i+7d]
> > Can you explain me how I could do it?

>
> I'm virtually certain you asked this same question some days ago and I
> told you then the same thing...
>
> Use interp1() as the above example w/ an interpolating vector of the
> points at which you want interpolants. Here's why I think I remember
> the question and the response, as I pointed out then, since interp1()
> works on columns you'll need to transpose, interpolate, then transpose back.
>
> I can't interpret the above [a a+d a+2d ... ) precisely but assuming d
> here is a different 'd' than that of the value in the original M(2,1)
> and is just a delta then the interpolant would seem to be
> linspace(0,N*d,N+1) where N is the number of intervals (7 above) added
> to a, b, c, ..., etc.
>
> --

------------------------------------
Dear dpb
thank you so much, I'm Beginner in matlab,
I apologize for my request
Is it possible give me matlab code of my question?
I couldn't use 'for' command or M(:,columns) ...
my matrix is 1000-by-1200
d=delta=1/16
its values (arrays) is arbitrary here

Date Subject Author
12/26/12 maryam
12/26/12 dpb
12/26/12 maryam
12/26/12 dpb
12/26/12 maryam
12/27/12 dpb
12/28/12 maryam
12/28/12 maryam
12/28/12 maryam
12/28/12 dpb
12/30/12 Steven Lord
12/31/12 dpb
4/9/15 rakeshElango
4/9/15 Steven Lord