How i can plot the entropy function H(p1,p2,p3) for three vector of probability p1, p2 and p3= (1-p1-p2)

hello every one.

How i can plot the entropy function H(p1,p2,p3) for three vector of probability p1, p2 and p3= (1-p1-p2) ... I tried this script but it seems to be wrong! could any one help me plz Many Thanks

clear all

clc

p_0=[0:0.01:0.5];

p_1=[0:0.01:0.5];

[P_0,P_1] = meshgrid(p_0,p_1);

H = (-P_0.*log2(P_0)-(P_1).*log2(P_1)-(1-P_0-P_1).*log2((1-P_0-P_1)));

surf(P_0,P_1,H)

[Ameer Hamza]

"it seems to be wrong"

MATLAB just plot what you tell it to the plot. If it seems wrong please tell why you think so. If it is wrong, there is a high chance that you wrote the equation wrong. Can you attach the image of the actual equation?

[Tammun filistin]

the correct answer supposed to be as the attached page from "Information Theory Jan C. A. van der Lubbe"

[Tammun filistin]

I have attached the equation also here Thank you,

Answer 1

[Ameer Hamza]

Your formula does not include the term -(1-P_0-P_1).*log2((1-P_0-P_1)), For 2D case, you can get something similar using this.

clear all
clc
p_0=0:0.01:1;
p_1=0:0.01:1;
[P_0,P_1] = meshgrid(p_0,p_1);
H = -P_0.*log2(P_0)-(P_1).*log2(P_1);
contour(P_0,P_1, H, 'ShowText', 'on')

[Tammun filistin]

im using 3 outcome probabilities which is p_0,p_1,p2=1-p_0-p_1 thats why im using this -(1-P_0-P_1).*log2((1-P_0-P_1)). Thank you