Matlab拒绝采样点不显示

Question

我使用以下代码进行Pi逼近，使用拒绝采样方法。

% DISPLAY A CIRCLE INSCRIBED IN A SQUARE 

figure; 
a = 0:.01:2*pi; 
x = cos(a); y = sin(a); 
hold on 
plot(x,y,'k','Linewidth',2) 

t = text(0.5, 0.05,'r'); 
l = line([0 1],[0 0],'Linewidth',2); 
axis equal 
box on 
xlim([-1 1]) 
ylim([-1 1]) 
title('Unit Circle Inscribed in a Square') 

pause; 
rand('seed',12345) 
randn('seed',12345) 
delete(l); delete(t); 

% DRAW SAMPLES FROM PROPOSAL DISTRIBUTION 
samples = 2*rand(2,100000) - 1; 

% REJECTION 
reject = sum(samples.^2) > 1; 

% DISPLAY REJECTION CRITERION 
scatter(samples(1,~reject),samples(2,~reject),'b.') 
scatter(samples(1,reject),samples(2,reject),'rx') 
hold off 
xlim([-1 1]) 
ylim([-1 1]) 

预期结果应该是红色圆圈内的蓝色圆圈。当我运行代码时，会显示构建正方形的红点，但蓝点不会显示。 预期的结果应于本Link

发现的图片，但我得到以下结果：

有谁知道我能以可视化的蓝点以及可能的吗？提前致谢。

Answer 1

scatter函数可能是not the best choice对于如此巨大的点数。试试这个：

t = 0:.01:2*pi; 
x = cos(t); y = sin(t); 

samples = 2*rand(2,100000) - 1; 
reject = sum(samples.^2) > 1; 

props = {'LineStyle','none', 'Marker','.', 'MarkerSize',1}; 
line(x, y, 'Color','k', 'LineWidth',2) 
line(samples(1,~reject), samples(2,~reject), props{:}, 'Color','b') 
line(samples(1,reject), samples(2,reject), props{:}, 'Color','r') 
axis equal; axis([-1 1 -1 1]) 
box on