Make probability matrix from data set

Question

Dylan Girodat 2020-3-6

0
链接

此问题的直接链接

https://ww2.mathworks.cn/matlabcentral/answers/509494-make-probability-matrix-from-data-set

回答： Koushik Vemula 2020-3-9

I have a data set that consists of time and multiple distances, it is formated as:

Time Distance 1 Distance 2 Distance 3 ...

0 2 1 2

1 3 3 4

2 4 4 5

3 5 6 4

4 7 6 4

I would like to transform the information into a probability matrix to make a heat plot. On the graph I would like the X axis to be the time column, the Y axis to be distances, and the Z-axis to be the probability of each distance occuring at the respective time.

Any help would be much appreciated,

Thank you,

Dylan

1 个评论
显示 -1更早的评论隐藏 -1更早的评论

Dylan Girodat 2020-3-6

Sorry I should say the output that would work for me would be:

Time Distance Probability

0 1 X

0 2 X

0 3 X

0 4 X

0 5 X

0 6 X

0 7 X

1 1 X

1 2 X

1 3 X

1 4 X

1 5 X

1 6 X

1 7 X

2 1 X

....

请先登录，再进行评论。

请先登录，再回答此问题。

Answer 1

Koushik Vemula 2020-3-9

0
链接

此回答的直接链接

https://ww2.mathworks.cn/matlabcentral/answers/509494-make-probability-matrix-from-data-set#answer_419156

在 MATLAB Online 中打开

According to my understanding, you’d like to have a matrix (say ‘Prob’) which stores the data values in an n-by-3 matrix where first column contains time, second column contains distance value and third column contains the probability of distance.

You can do it in the following manner.

data=[[2,1,2];[3,3,4];[4,4,5];[5,6,4];[7,6,4]]; %Example Dataset 
[m,n]=size(data); 
k=1; 
[0,1,sum(data(1,:)==1)/length(data(1,:))]; 
for i = 1:m 
x=unique(data(i,:)','rows'); 
for j = 1:length(x) 
Prob(k,:)=[i-1,x(j),sum(data(i,:) == x(j))/(length(data(i,:)))]; 
k=k+1; 
end 
end 

As you can see the desired output is stored in the variable ‘Prob’. Here ‘data’ represents the data set that consists of time and multiple distances where time is ‘index-1’ and values will be your distances