Convert table into 2D matrix

Question

Juan Troya 2022-11-21

0
链接

此问题的直接链接

https://ww2.mathworks.cn/matlabcentral/answers/1858418-convert-table-into-2d-matrix

回答： KSSV 2022-11-21

I want to do data 2D binning of a variable "signal" by 2 other variables 'speed' and 'direction'

a1=0;
b1=360;
N=100;
N = 100
direction = a1 + (b1-a1).*rand(N,1);
a2=1;
b2=16;
speed = a2 + (b2-a2).*rand(N,1);
a3=-5;
b3=5;
signal = a3 + (b3-a3).*rand(N,1);
ndirections             = 36;
dirBins = linspace(0,360,ndirections+1);   %wind direction bins of 10deg
vmax      = ceil(max(speed));
windBins    = linspace(1,vmax,vmax);    
[Yspd,Espd] = discretize(speed,windBins);%bins index of wind speed
[Ydir,Edir] = discretize(direction,dirBins);%bins index of wind direction
data = array2table([direction, speed,Ydir, Yspd,signal], 'VariableNames', {'Direction', 'Speed','DirBinIdx','SpeedBinIdx', 'Signal'})
data = 100×5 table
DirectionSpeedDirBinIdxSpeedBinIdxSignal___________________________________________

     6.7114      7.7659        1             7          -4.5375
      267.9      7.5038       27             7          0.50178
     64.713       8.929        7             8           2.3849
     192.98      4.0114       20             4          -4.3776
      19.68      13.746        2            13         -0.51325
     128.41      5.5993       13             5          -1.7249
      316.3      12.593       32            12           3.3347
     322.43      8.2344       33             8          -4.1392
     244.95      8.3105       25             8          0.16218
      184.3      15.197       19            15          -2.2387
     273.64      1.4889       28             1           -2.952
     333.49       6.263       34             6         -0.30713
     120.49      5.5329       13             5           3.6812
     85.721      15.615        9            15           3.2914
     329.52      5.7136       33             5          -3.4584
     264.41      1.2378       27             1          -4.7495
binAvg = groupsummary(data, ["DirBinIdx", "SpeedBinIdx"], "mean","Signal")
binAvg = 95×4 table
DirBinIdxSpeedBinIdxGroupCountmean_Signal_________________________________________

        1             7             1           -4.5375  
        1            11             1          -0.23016  
        1            13             1            1.4332  
        2             3             1           -1.5489  
        2            13             1          -0.51325  
        3            14             1          -0.34484  
        3            15             1           0.61782  
        4             1             1            3.5306  
        4            12             1            1.3497  
        5             7             1           -0.9348  
        7             6             1           -4.5022  
        7             8             1            2.3849  
        8             1             1            1.4526  
        8             8             1            1.3615  
        8            11             1            1.9656  
        8            15             1             1.697  

Given binAvg, I would like to convert it in a matrix with columns from "DirBinIdx", rows from "SpeedBinIdx" and the values of the matrix given by 'Signal'