count the values based on ID and create a new matrix

Input:

LAT LON VALUE

12.4 91.4 4

31.4 45.6 1

45.9 91.5 2

18.4 96.4 3

11.4 75.6 2

25.9 51.5 4

12.4 91.4 4

31.4 45.6 2

45.9 91.5 2

As you can see some of the lat lon's are repeated with different values, so I want to know for a lat lon, how many times (count) a values is observed. I have a input matrix of (90,000, 3)

LAT LON cnt = 1 cnt=2 cnt=3 cnt =4

12.4 91.4 0 0 1 2

31.4 45.6 1 1 0 0

45.9 91.5 0 1 2 0

18.4 96.4 0 0 1 0

11.4 75.6 0 1 0 0

25.9 51.5 0 0 0 1

I tried table, I could not figure out.

[KALYAN ACHARJYA]

Is it OK with cell arrays?

sample={'LAT' 'LON' 'cnt=1' 'cnt=2' 'cnt=3' 'cnt=4';12.4 91.4 1 0 3 0;31.4 45.6 2 4 0 9;45.9 91.5 10 0 9 20}

sample =

'LAT' 'LON' 'cnt=1' 'cnt=2' 'cnt=3' 'cnt=4'

[12.4000] [91.4000] [ 1] [ 0] [ 3] [ 0]

[31.4000] [45.6000] [ 2] [ 4] [ 0] [ 9]

[45.9000] [91.5000] [ 10] [ 0] [ 9] [ 20]

[nlm]

makes no sense.

[madhan ravi]

Give an example of your desired output explicitly.

[nlm]

Input:

LAT LON VALUE

12.4 91.4 4

31.4 45.6 1

45.9 91.5 2

18.4 96.4 3

11.4 75.6 2

25.9 51.5 4

12.4 91.4 4

31.4 45.6 2

45.9 91.5 2

As you can see some of the lat lon's are repeated with different values, so I want to know for a lat lon, how many times (count) a values is observed. I have a input matrix of (90,000, 3)

LAT LON cnt = 1 cnt=2 cnt=3 cnt =4

12.4 91.4 0 0 1 2

31.4 45.6 1 1 0 0

45.9 91.5 0 1 2 0

18.4 96.4 0 0 1 0

11.4 75.6 0 1 0 0

25.9 51.5 0 0 0 1

Look foward to your help. Thank you

[nlm]

[ii,jj,kk]=unique(M,'rows','stable');

out=[ii,accumarray(kk,1)];

I get the count for each value, like this

963 66 4 3

963 67 3 1

963 68 3 1

963 69 3 1

963 67 4 2

963 68 4 2

963 69 4 2

however, I cannot get it in the form like this,

val=1 val=2 val=3 val=4

963 66 0 0 0 3

963 67 0 0 1 2

963 68 1 2

963 69 1 2

[madhan ravi]

Which version of matlab are you using?

[nlm]

2018a

[madhan ravi]

Well good then :

t=[12.4      91.4      4       
   31.4      45.6      1        
   45.9      91.5      2      
   18.4      96.4      3       
   11.4      75.6      2       
   25.9      51.5      4       
   12.4      91.4      4       
   31.4      45.6      2        
   45.9      91.5      2];   
T=array2table(t,'VariableNames',{'LAT','LON','COUNT'})
groupsummary(T,{'LAT','LON','COUNT'}) % gives almost your result but in more compact way

[nlm]

I have already tried it, as mentioned earlier. It does not give me the form that I'm looking for. I need it like this

LAT LON cnt = 1 cnt=2 cnt=3 cnt =4

12.4 91.4 0 0 1 2

31.4 45.6 1 1 0 0

45.9 91.5 0 1 2 0

18.4 96.4 0 0 1 0

11.4 75.6 0 1 0 0

25.9 51.5 0 0 0 1

Answer 1

[Image Analyst]

Use unique() to get unique rows. Then for each unique row (lat,lon combination), call histogram.

[nlm]

[a,~,c] = unique((M),'rows');, 
Hist =histogram(a); 

It's a figure, could I get it in matrix form ?

[Image Analyst]

Hist is an object. Look at it's properties and methods and you'll know what to do. Take the semicolon off of that line to see the properties.

[nlm]

I did, doesn't help.

Error in matlab.graphics.chart.primitive.Histogram/get.BinCounts