Finding a vector with a table

Hi,

I have a table:

23x4 double  56.3507527250652  'BRANCH'
13x4 double  64.3500399298111  'BRANCH'
19x4 double  92.8117570643396  'BRANCH'
32x4 double  115.752266229064  'BRANCH'
4x4 double  27.1259128701332  'BRANCH'
132x4 double  359.891498931659  'BRANCH'
6x4 double  34.5092311768868  'BRANCH'
31x4 double  83.1975489342949  'BRANCH'
47x4 double  136.221229624204  'BRANCH'
37x4 double  63.5355126390744  'BRANCH'

I want to extract data from the first column, each column is ordered like this, think of it as x,y,z,d:

46.6495524000000  47.8684800000000  17.3488650000000  2.59074640000000
45.2452924000000  47.7032600000000  17.0319650000000  2.31435600000000
43.8410324000000  47.5382600000000  16.7151150000000  2.03796120000000
42.4367724000000  47.3732600000000  16.3982150000000  1.76157080000000
39.3039724000000  46.5128400000000  16.0034650000000  0.796791600000000
37.4286924000000  45.4902800000000  14.9268150000000  0.729537600000000

I want to find the values which are identical to other values extracted from the set. I have extracted here x,y,z:

     48.9702   94.8262    9.3419
     47.7602   95.9105    8.7308

corresponding to the first three columns of the first column of the table: x,y,z.

I want to be able to find the position of the values in the table. So far I have come up with this:

     y76 = neuron((no_synapses),[3:5]);
     y76(:,1) = y76(:,1) * xy_pixel;
     y76(:,2) = y76(:,2) * xy_pixel;
     y76(:,3) = y76(:,3) * z_stack;

     SYNAPSE = cell(size(branches));
     for i = 1:length(branches)
        for j = 1:length(no_syn)
            for k = 1:size(branches{i},1)
                  SYNAPSE = find([branches{i}(k,1:3) == y76(j,:)])
            end
        end
     end

But haven't had any luck with it. This just appears:

SYNAPSE =

    1×0 empty double row vector

Does anyone have any suggestions.

Cheers.

Answer 1

[Walter Roberson]

http://matlab.wikia.com/wiki/FAQ#Why_is_0.3_-_0.2_-_0.1_.28or_similar.29_not_equal_to_zero.3F