1. 二维高层绘图操作
1.plot函数
%绘制正弦函数，x在0到2PI之间，
x = 0:0.01:2*pi;
y = sin(x);
plot(x, y);
%第二个参数为矩阵
y1 = sin(x);
y2 = cos(x);
y3 = 0.002*exp(x);
y4 = x;
y5 = 0.002*tan(x);
%用5个y形成一个向量
z = [y1; y2; y3; y4; y5];
%绘制5条曲线，分别是 正弦函数，余弦函数，指数函数，直线，正切函数
plot(x, z)
%两个参数都是矩阵
x1 = 0:0.01:2*pi;
x2 = -pi:0.01:pi;
x = [x1; x2]';
y1 = cos(x1);
y2 = sin(x2);
y = [y1; y2]';
plot(x, y)
% plot只有一个参数
x = linspace(0, 2*pi, 200); %从0到2pi之间产生200个点
y = sin(x);
plot(y)
y2 = cos(x);
y3 = y + i*y2;
plot(y3)
axis equal
% plot多个参数
x1 = linspace(0, 2*pi, 200);
x2 = linspace(0, 2*pi, 100);
y1 = cos(x1);
y2 = sin(x2);
plot(x1, y1, x2, y2)
% plot含有的曲线选项
x = linspace(0, 2*pi, 100);
y = sin(x);
plot(x, y, 'k') % r g y m k b 颜色
plot(x, y, 'p') % * . p < > 标注符号
plot(x, y, ':') % - -- -. :
plot(x, y, 'r*:')
%图形标注
x = linspace(0, 2*pi, 100);
y = sin(x);
plot(x, y)
xlabel('x')
ylabel('y')
title('????');
text(2, 0.3, 'y = xin(x)');
text(5, 0.5, 'x_2')
x1 = linspace(0, 2*pi, 200);
x2 = linspace(0, 2*pi, 100);
y1 = cos(x1);
y2 = sin(x2);
plot(x1, y1, x2, y2)
legend('cos', 'sin');
%设置显示区间
xlim([0 10])
%%图形保持
x = 0:0.1:2*pi;
y1 = sin(x);
y2 = cos(x);
hold on
plot(x, y1, 'r');
plot(x, y2, 'g');
hold off
%%窗口分割
x = 0:0.1:2*pi;
y1 = sin(x);
y2 = cos(x);
y3 = tan(x);
y4 = exp(x);
subplot(2, 2, 1)
plot(x, y1);
subplot(222)
plot(x, y2)
subplot(223)
plot(x, y3)
subplot(224)
plot(x, y4)
2.matlab底层绘图操作
基本的底层绘图函数
% line对象
% h = line([-pi:0.01:pi], sin([-pi:0.01:pi]));
% hp = plot([-pi:0.01:pi], sin([-pi:0.01:pi]));
%使用line绘图并设置属性
hl = line('XData', [-pi:0.1:pi], 'YData', sin([-pi:0.1:pi]), ...
'LineWidth', 1, 'LineStyle', ':', 'Color', 'r');
%使用set继续添加属性值
set(hl, 'LineWidth', 2, 'Marker', 'p', 'MarkerSize', 15);
底层标注
ht = text(0, 0, 'sin');
set(ht, 'String', 'cos');
set(ht, 'FontSize', 20);
底层坐标轴的控制
%绘图中，一般先使用figure函数生成窗口，然后用axes生成坐标轴，最后用line函数，plot函数绘图标注
hf = figure;
ha = axes('Parent', hf, 'Units', 'normalized', 'Position', [.1 .1 .6 .5]);