用matlab完成下面的程序：Define =[200*sinx/x, x^2], and draw the graph of the function in the range x=[-20，20]

在MATLAB中，你可以使用`fplot`函数来绘制给定定义的二维函数图形。首先，你需要定义变量`x`的范围，然后创建向量，接着定义你要画出的两个函数。下面是完成这个程序的步骤：

% 定义x的范围
x = -20:0.1:20; % 使用步长0.1是因为更小的步长可以得到更精细的图像

% 定义函数
Define = [200*sin(x)./x, x.^2]; % 注意MATLAB中除法运算符是./而非/

% 绘制函数图形
figure; % 创建新的绘图窗口
[f1, f2] = Define; % 分离两个函数的结果
hold on; % 保持当前图像，以便在同一图上绘制两个曲线
plot(x, f1, 'b', 'LineWidth', 2); % 蓝色线表示第一个函数，宽度为2
plot(x, f2, 'r--', 'LineWidth', 1); % 红色虚线表示第二个函数，宽度为1
hold off; % 关闭保持状态

% 添加标题和坐标轴标签
title('Graph of Functions y = 200*sin(x)/x and y = x^2');
xlabel('x');
ylabel('Functions Values');

% 显示图形
grid on; % 添加网格线
xlim([-20, 20]); % 设置x轴范围
ylim([-150, 400]); % 设置y轴范围，根据实际计算可能需要调整

相关问题

用matlabTry to plot three dimensional graph of the function z=2*x^2+y^2 , where x=sin3t and y=cos3t . The range of t should be set to [-3, 3], and the ranges of x and y axes are both [-1.2, 1.2]. Requirement: Plot the three-dimensional (3-D) mesh graph, 3-D surface graph and 3-D surface graph with contour lines, respectively. In addition, plot the 2-D sectional view graph for x=1.

Sure, here's the code to plot the three-dimensional graph of the given function in MATLAB:

% Define the function
f = @(x, y) 2*x.^2 + y.^2;

% Define the range of t
t = linspace(-3, 3, 100);

% Calculate the x and y values
x = sin(3*t);
y = cos(3*t);

% Calculate the z values
z = f(x, y);

% Create a meshgrid for the x and y values
[X, Y] = meshgrid(x, y);

% Plot the 3D mesh graph
figure;
mesh(X, Y, z);
xlabel('X');
ylabel('Y');
zlabel('Z');
title('3D Mesh Graph');

% Plot the 3D surface graph
figure;
surf(X, Y, z);
xlabel('X');
ylabel('Y');
zlabel('Z');
title('3D Surface Graph');

% Plot the 3D surface graph with contour lines
figure;
surf(X, Y, z);
xlabel('X');
ylabel('Y');
zlabel('Z');
title('3D Surface Graph with Contour Lines');
hold on;
contour(X, Y, z, 20, 'k');
hold off;

% Plot the 2D sectional view graph for x=1
x1 = 1;
y1 = linspace(-1.2, 1.2, 100);
z1 = f(x1, y1);

figure;
plot(y1, z1);
xlabel('Y');
ylabel('Z');
title('2D Sectional View Graph for x=1');

This code will generate four figures, each containing the different types of plots you requested. The first figure is the 3D mesh graph, the second figure is the 3D surface graph, the third figure is the 3D surface graph with contour lines, and the fourth figure is the 2D sectional view graph for x=1. The ranges of the x and y axes are both [-1.2, 1.2], and the range of t is set to [-3, 3].

Try to plot three dimensional graph of the function z=2*x^2+y^2 , where x=sin3t and y=cos3t . The range of t should be set to [-3, 3], and the ranges of x and y axes are both [-1.2, 1.2]. Requirement: Plot the three-dimensional (3-D) mesh graph, 3-D surface graph and 3-D surface graph with contour lines, respectively. In addition, plot the 2-D sectional view graph for x=1.

Sure, I can help you with that. Here's the code in Python using matplotlib and numpy libraries:

import numpy as np
import matplotlib.pyplot as plt
from mpl_toolkits.mplot3d import Axes3D

# Define the function
def f(x, y):
    return 2*x**2 + y**2

# Define the range of t
t = np.linspace(-3, 3, 100)

# Calculate the x and y values
x = np.sin(3*t)
y = np.cos(3*t)

# Calculate the z values
z = f(x, y)

# Create a meshgrid for the x and y values
X, Y = np.meshgrid(x, y)

# Create a figure and three subplots for the different types of plots
fig = plt.figure(figsize=(12, 6))

ax1 = fig.add_subplot(2, 3, 1, projection='3d')
ax1.plot_wireframe(X, Y, z)
ax1.set_xlabel('X')
ax1.set_ylabel('Y')
ax1.set_zlabel('Z')
ax1.set_title('3D Mesh Graph')

ax2 = fig.add_subplot(2, 3, 2, projection='3d')
ax2.plot_surface(X, Y, z, cmap='viridis')
ax2.set_xlabel('X')
ax2.set_ylabel('Y')
ax2.set_zlabel('Z')
ax2.set_title('3D Surface Graph')

ax3 = fig.add_subplot(2, 3, 3, projection='3d')
ax3.plot_surface(X, Y, z, cmap='viridis')
ax3.contour(X, Y, z, zdir='z', offset=-1, cmap='viridis')
ax3.set_xlabel('X')
ax3.set_ylabel('Y')
ax3.set_zlabel('Z')
ax3.set_title('3D Surface Graph with Contour Lines')

# Create a 2D sectional view graph for x=1
x1 = 1
y1 = np.linspace(-1.2, 1.2, 100)
z1 = f(x1, y1)

ax4 = fig.add_subplot(2, 3, 4)
ax4.plot(y1, z1)
ax4.set_xlabel('Y')
ax4.set_ylabel('Z')
ax4.set_title('2D Sectional View Graph for x=1')

plt.show()

This code will generate a figure with six subplots. The first three subplots are the 3D mesh graph, 3D surface graph, and 3D surface graph with contour lines, respectively. The fourth subplot is the 2D sectional view graph for x=1. The ranges of the x and y axes are both [-1.2, 1.2], and the range of t is set to [-3, 3].