# MATLAB: Find, sort and assign values in matrix

accumarrayarrayfindsort

    
Hi im very new to matlab and cant get the following input to find and sort correctly.
An help is much appereciated ðŸ™‚
%input q3 =        1.0000    2.0000   90.0000    4.9424    2.0000    3.0000   91.0000    4.3018    3.0000    4.0000   92.0000    3.7912    4.0000    5.0000   93.0000    3.4618    5.0000    6.0000   94.0000    3.3465    6.0000    7.0000   95.0000    3.4566    7.0000    8.0000   96.0000    3.7815    8.0000    9.0000   97.0000    4.2892    9.0000   10.0000   98.0000    4.9293   10.0000   11.0000   99.0000    5.6382    ...              %wanted output       q4=        1.0000    (4.9424/3)    2.0000    (4.9424/3)+(4.3018/3)    3.0000    (4.3018/3)+(3.7912/3)    4.0000    (3.7912/3)+(3.4618/3)    5.0000    (3.4618/3)+(3.3465/3)    6.0000    (3.3465/3)+(3.4566/3)    ...     98.0000   (4.9293/3)    99.0000   (5.6382/3)        
The numbers is column 1, 2 and 3 are the numbers of my nodes. Each row is the nodes of a triangle and the area of that triangle.
Now need the area of each triangle to be divided out onto each node of that triangle. At last i need all of the areas that are divided onto node number 1 to be sumed up and so forth for each node.

q3 = [       1.0000    2.0000   90.0000    4.9424    2.0000    3.0000   91.0000    4.3018    3.0000    4.0000   92.0000    3.7912    4.0000    5.0000   93.0000    3.4618    5.0000    6.0000   94.0000    3.3465    6.0000    7.0000   95.0000    3.4566    7.0000    8.0000   96.0000    3.7815    8.0000    9.0000   97.0000    4.2892    9.0000   10.0000   98.0000    4.9293   10.0000   11.0000   99.0000    5.6382];q_ = q3(:,1:3);vals1 = unique(q_);vals2 = zeros(size(vals1));for i = 1:numel(vals1)    idx = any(q_==vals1(i),2);    vals2(i) = sum(q3(idx,4));endq4 = [vals1 vals2/3];
>> q4q4 =    1.0000    1.6475    2.0000    3.0814    3.0000    2.6977    4.0000    2.4177    5.0000    2.2694    6.0000    2.2677    7.0000    2.4127    8.0000    2.6902    9.0000    3.0728   10.0000    3.5225   11.0000    1.8794   90.0000    1.6475   91.0000    1.4339   92.0000    1.2637   93.0000    1.1539   94.0000    1.1155   95.0000    1.1522   96.0000    1.2605   97.0000    1.4297   98.0000    1.6431   99.0000    1.8794