1. Bar graph drawing
Drawing bar graphs can be divided into two-dimensional and three-dimensional cases: bar (vertical bar graph), barh (horizontal bar graph), bar3 (three-dimensional vertical bar graph), bar3h (three-dimensional horizontal bar graph) , the format of the function call in these cases is the same:
bar(y): use y as the component to display the height respectively, and the abscissa is [1, length(y)]; if y is a matrix, the situation is similar;
bar(x,y): draws y on the specified x, where x is a strictly single-increasing vector;
bar(...,width): width is the spacing of the bars in the group, the default value is 0.8 (very small spacing), if you set width=1, the bars in the group will touch each other;
bar(...,'style'): style specifies the type of arrangement, there are "group" (default) and "stack". If Y is a matrix of m*n size, group means that each group has n bars and m groups, and stack means that there are m bars and each color is different, and the height of each bar is the sum of the row vectors.
x = [1:10];
y = [75, 58, 90, 87, 50, 85, 92, 75, 60, 95];
figure(2);
bar(x,y), xlabel('Student'),ylabel('Score'),
title('First Sem:')2. Pie chart drawing
Pie charts are used to display the proportion of each element in a vector or matrix. Two-dimensional is pie, three-dimensional is pie3, and the calling format is similar.
pei(X): Draw a pie chart with the data in X. If sum(X)<1, the pie chart drawn is incomplete;
pei(X,explode): Offset each part of the sector by a certain position, where explode is a matrix with the same dimension as X. When all elements are 0, each part of the sector will form a circle.
X = [528 718 624 859];
explode = [0 1 0 1];
pie3(X,explode);
title('三维分离饼图');3. Area chart drawing
The drawing of the area chart can actually show the influence of different parts on the whole, and its command is area.
area(Y): Draw each column in the vector or matrix Y as a separate curve and stack it;
area(X,Y): Draw a graph of Y versus X, filling the area between 0 and Y;
area(...,basevalue): basevalue specifies the base value for filling the area, and the default is 0.
Y = [45 4 6; 24 6 9; 19 4 3; 9 2 4; 25 8 15; 7 14 9];
area(Y);
grid on;
set(gca,'layer','top'); %将坐标的图层上移到顶层
title('面积图');4. Drawing of contour lines
[C, h] = contour(x,y,g);
returns the contour matrix C (containing the data defining the contours) and the Contour object h. Plot the contours of z with x,y.
meshgrid function: Generate two arrays:
one is y column x row, each row is the same, each column is in order (-5, -4.9,..., 5)
one is x row y column, each column is Same, each row is (-3, -2.9,...,3)Τ in order
[x,y] = meshgrid(-5:0.1:5,-3:0.1:3);
g = x.^2 + y.^2; %数组运算为要加 ‘.’
[C, h] = contour(x,y,g);
set(h,'ShowText','on','TextStep',get(h,'LevelStep')*2)
% get(h,'LevelStep')*2，显示值为LevelStep的2倍的值，让画出来的等高线一条隔一条地显示set and get are functions for setting and obtaining the attribute value of the handle object;
ShowText is on to display the value of the contour line, off is not to display the value of the contour line, and the default is off;
LevelStep is m to display the value in multiples of m Contours, obviously the larger m is, the sparser the drawn contours will be;
TextStep is n, which means the value of the contours whose value is a multiple of n will be displayed, and the values of other contours will not be displayed;
5. Polar coordinate drawing
The coordinates of the polar coordinate system are (ρ, θ)
polarplot draws points on polar coordinates;
polarscatter draws a scatter plot on polar coordinates;
polarhistogram draws a histogram on polar coordinates;
compass draws an image with arrows
on polar coordinates ; function plot on
figure(1);
angle=0:0.1:2*pi;
length1=2*angle;
polarplot(angle,length1,'--r');
figure(2);
length2=sin(angle);
polarplot(angle,length2,':b');
%极坐标中不支持在绘图函数中设定自变量的范围，可调用函数rlim
figure(3);
polarplot(angle,length2,'b');
rlim([-1 1]);
figure(4);
polarscatter(angle,length1,'filled'); %不添加 filled 命令则默认为空心圆点
figure(5);
polarhistogram(length2) %直方图是对数据点进行统计，然后绘制频数
figure(6);
compass([1 0 0 -1],[0 1 -2 1]); %两个向量，第一个是四个横坐标，第二个是对应的纵坐标
%例如第一个箭头在平面坐标上(0,0)指向(1,0),转换到极坐标就是θ=0，ρ=1
figure(7);
ezpolar(@(angle)2*angle)
figure(8);
ezpolar(@sin);6. Drawing of 3D graphics
Most of the function formats for drawing three-dimensional graphics are similar to two-dimensional, except that a third-dimensional information is added to the parameters.
surf : plot a surface mesh : plot a mesh
surfc : plot a surface with contours meshc : plot a mesh with contours meshz
: plot a mesh with curtains
fsurf : plot a function-based surface fmesh : draw function-based
The usage format of the above functions is similar, just take the mesh function as an example:
mesh(X,Y,Z): draw a three-dimensional mesh, the color matches the height of the surface;
mesh(Z): The generated grid map satisfies X=1:n and Y=1:m, [n,m]=size(Z);
mesh(Z,c): Same as mesh(Z), and further specify the edge color by c.
x0=1:5;
y0=6:11;
[x,y]=meshgrid(x0,y0); %把两个向量转变为两个矩阵
z=x.^3+y.^3;
figure(1);
c=randi(20,size(z)); %设定一个颜色变量，其大小要和函数 z 相同
surf(x,y,z,c,'linestyle','--'); %对线条颜色设定时要通过 属性对linestyle 进行设置
colorbar; %插入颜色栏
figure(2);
h=surf(x,y,z); %获取图像的句柄
h.FaceAlpha=0.5; %调整透明度 1-完全不透明 0-完全透明
figure(3);
surfc(x,y,z); %下方的曲线就是等高线
figure(4);
mesh(x,y,z);
figure(5);
meshc(x,y,z);
figure(6);
meshz(x,y,z);
figure(7);
z=@(x,y)x.^3+y.^3;
h=fsurf(z); %会把数据点取的很密
h.EdgeColor=[1 0 0];
h.LineStyle=('--');
figure(8);
z=@(x,y)x.^3+y.^3;
fmesh(z);