is there a name for this and/or perhaps
in [Matlab]
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From: jenya polyakova on 19 Feb 2010 12:27 a matlab function? I have a vector of data DATA and also respective X and Y coordinate vectors of the same length as data. I need to divide my area into rectangular boxes and then calculate the mean (based on my DATA) for each of these box. Is there a function like that in Matlab? Thanks
From: ImageAnalyst on 19 Feb 2010 12:32 On Feb 19, 12:27 pm, "jenya polyakova" <jeny...(a)yahoo.com> wrote: > a matlab function? I have a vector of data DATA and also respective X and Y coordinate vectors of the same length as data. I need to divide my area into rectangular boxes and then calculate the mean (based on my DATA) for each of these box. Is there a function like that in Matlab? Thanks ------------------------------------------ Use blkproc() and mean() It's been recently discussed: http://www.mathworks.com/matlabcentral/newsreader/view_thread/272121#714461
From: jenya polyakova on 19 Feb 2010 12:53 Thanks for reply. I was wondering if we run, for example, T=rand(686,6); P = blkproc(T,[10 1], @mean); It returns P of size 69x6. I would like it to return the same dimensions as T except that it would have appropriate block means (i.e. P) in each node. Thanks. ImageAnalyst <imageanalyst(a)mailinator.com> wrote in message <932a5ac8-bd72-48e8-93a9-ff301e1dd7fb(a)g28g2000yqh.googlegroups.com>... > On Feb 19, 12:27 pm, "jenya polyakova" <jeny...(a)yahoo.com> wrote: > > a matlab function? I have a vector of data DATA and also respective X and Y coordinate vectors of the same length as data. I need to divide my area into rectangular boxes and then calculate the mean (based on my DATA) for each of these box. Is there a function like that in Matlab? Thanks > > ------------------------------------------ > Use blkproc() and mean() > It's been recently discussed: > > http://www.mathworks.com/matlabcentral/newsreader/view_thread/272121#714461
From: Ashish Uthama on 19 Feb 2010 13:01 On Fri, 19 Feb 2010 12:53:04 -0500, jenya polyakova <jenya56(a)yahoo.com> wrote: > Thanks for reply. I was wondering if we run, for example, T=rand(686,6); > P = blkproc(T,[10 1], @mean); > It returns P of size 69x6. > I would like it to return the same dimensions as T except that it would > have appropriate block means (i.e. P) in each node. Thanks. > Look at the doc for IMFILTER, FSPECIAL : >> a=magic(5) a = 17 24 1 8 15 23 5 7 14 16 4 6 13 20 22 10 12 19 21 3 11 18 25 2 9 >> imfilter(a,fspecial('average',3)) ans = 7.6667 8.5556 6.5556 6.7778 5.8889 8.7778 11.111 10.889 12.889 10.556 6.6667 11 13 15 10.667 6.7778 13.111 15.111 14.889 8.5556 5.6667 10.556 10.778 8.7778 3.8889 >> mean([23 5 7 4 6 13 10 12 19]) %consider the (3,2) element (6) in 'a'. >> The 3x3 average around it is: ans = 11 >>
From: jenya polyakova on 19 Feb 2010 13:29
I am not sure I understand. What if I want blocks of size 10x10. I think mat2cell might work for me but I am yet to figure out how it works: where is there starting position if, say, I have 235x56 matrix and want to divide it into 2.5x2.5 blocks? Thanks "Ashish Uthama" <first.last(a)mathworks.com> wrote in message <op.u8dy0q17a5ziv5(a)uthamaa.dhcp.mathworks.com>... > On Fri, 19 Feb 2010 12:53:04 -0500, jenya polyakova <jenya56(a)yahoo.com> > wrote: > > > Thanks for reply. I was wondering if we run, for example, T=rand(686,6); > > P = blkproc(T,[10 1], @mean); > > It returns P of size 69x6. > > I would like it to return the same dimensions as T except that it would > > have appropriate block means (i.e. P) in each node. Thanks. > > > > > Look at the doc for IMFILTER, FSPECIAL : > > >> a=magic(5) > > a = > > 17 24 1 8 15 > 23 5 7 14 16 > 4 6 13 20 22 > 10 12 19 21 3 > 11 18 25 2 9 > > >> imfilter(a,fspecial('average',3)) > > ans = > > 7.6667 8.5556 6.5556 6.7778 5.8889 > 8.7778 11.111 10.889 12.889 10.556 > 6.6667 11 13 15 10.667 > 6.7778 13.111 15.111 14.889 8.5556 > 5.6667 10.556 10.778 8.7778 3.8889 > > >> mean([23 5 7 4 6 13 10 12 19]) %consider the (3,2) element (6) in 'a'. > >> The 3x3 average around it is: > > ans = > > 11 > > >> |