平滑粗糙的地块(Smoothing out of rough plots)

 我想在Matlab中绘制一些图。 
 
 细节：对于1类， p（x | c1）对于[2,4]之间的x是均匀的，参数a = 1且b = 4 。 对于类2 ， p（x | c2）是指数的，参数lambda = 1 。 除了p（c1）= p（c2）= 0.5之外，我想绘制两个类密度的草图，分别乘以P（c1）和P（c2） ，作为x的函数，清楚地显示最优决策边界（或边界）。 
 
 我有解决这个问题的方法，这就是作者所做的（ 我想得到 ），但是没有Matlab代码，所以我想自己做。 
 
 
 这就是我画的。 
 
 
 这是我写的MATLAB代码。 
 
x=0:1:8;

pc1 = 0.5;
px_given_c1 = exppdf(x,1);
px_given_c2 = unifpdf(x,2,4);

figure;
plot(x,px_given_c1,'g','linewidth',3);
hold on;
plot(x,px_given_c2,'r','linewidth',3);
axis([0 8 0 0.5]);
legend('P(x|c_1)','P(x|c_2)');

figure;
plot(x,px_given_c1.*pc1,'g','linewidth',3);
hold on;
plot(x,px_given_c2.*(1-pc1),'r','linewidth',3);
axis([0 8 0 0.5]);
legend('P(x|c_1)P(c_1)','P(x|c_2)P(c_2)');
 
 正如你所看到的，它们几乎是熟悉的，但我对这种均匀分布有问题，这是用红色绘制的。 我该怎么改变它？ 

I want to draw some plots in Matlab.
 
Details: For class 1, p(x|c1) is uniform for x between [2, 4] with the parameters a = 1 and b = 4. For class 2, p(x|c2) is exponential with parameter lambda = 1. Besides p(c1) = p(c2) = 0.5 I would like to draw a sketch of the two class densities multiplied by P(c1) and P(c2) respectively, as a function of x, clearly showing the optimal decision boundary (or boundaries).
 
I have the solution for this problem, this is what the writer did (and I want to get), but there's no Matlab code, so I want to do it all by myself.
 
 
And this is what I drew.
 
 
And this is the MATLAB code I wrote.
 
x=0:1:8;

pc1 = 0.5;
px_given_c1 = exppdf(x,1);
px_given_c2 = unifpdf(x,2,4);

figure;
plot(x,px_given_c1,'g','linewidth',3);
hold on;
plot(x,px_given_c2,'r','linewidth',3);
axis([0 8 0 0.5]);
legend('P(x|c_1)','P(x|c_2)');

figure;
plot(x,px_given_c1.*pc1,'g','linewidth',3);
hold on;
plot(x,px_given_c2.*(1-pc1),'r','linewidth',3);
axis([0 8 0 0.5]);
legend('P(x|c_1)P(c_1)','P(x|c_2)P(c_2)');
 
As you can see, they are almost smiliar, but I am having problem with this uniform distribution, which is drawn in red. How can I change it?

原文：https://stackoverflow.com/questions/13309089