Create array from table with observations with two codes

I want to create a matrix based on a table with observations which have two codes to each observation.

Based on the table x I want to get the array at the bottom. I know how I can generate it by making a heatmap, but I am sure there is a much better way. Hopefully there is a function so that I don't need to generate a heatmap and copy the variable from there.

>> x = readtable("C:\matlap_files\tst.csv")

x =

  6×3 table

    observations    code1    code2
    ____________    _____    _____

        100         {'a'}    {'a'}
         15         {'b'}    {'b'}
         25         {'c'}    {'d'}
        111         {'d'}    {'d'}
        200         {'e'}    {'f'}
        175         {'f'}    {'f'}

>> h = heatmap(x,'code1','code2','ColorVariable',"observations",'ColorMethod','sum')

h = 

  HeatmapChart (Sum of observations) with properties:

      SourceTable: [6×3 table]
        XVariable: 'code1'
        YVariable: 'code2'
    ColorVariable: 'observations'
      ColorMethod: 'sum'

  Show all properties

>> h.ColorData

ans =

   100     0     0     0     0     0
     0    15     0     0     0     0
     0     0    25   111     0     0
     0     0     0     0   200   175

Answer 1

[Star Strider]

The accumarray function is perfect for this:

x = readtable('Wtst.csv');
[G,code1,code2] = findgroups(x.code1,x.code2);
[Ux1,~,ix1] = unique(x.code1,'stable');
[Ux2,~,ix2] = unique(x.code2,'stable');

tally = accumarray([ix2,ix1], x.observations, [], @sum)

producing:

tally =
   100     0     0     0     0     0
     0    15     0     0     0     0
     0     0    25   111     0     0
     0     0     0     0   200   175

.

[William Ambrose]

what a gem! Works so well, thank you very much.

[Star Strider]

I very much appreciate your compliment!

As always, my pleasure!

[William Ambrose]

:-)