MATLAB Fundamentals>>>(2/2) Project - Analyze Vehicle Data

#创作灵感#

MATLAB基础知识官方课程学习笔记


MATLAB Fundamentals>Common Data Analysis Techniques>Summary of Common Data Analysis Techniques>(2/2) Project - Analyze Vehicle Data


任务名称:Fuel Economy Analysis


任务1:

The variable mpg contains NaN values. Find the rows in mpg with NaN values, and remove those rows from all three data vectors: mpg, hp, and wt.

解答1:

Matlab 复制代码
nanIdx = ismissing(mpg)
mpg = mpg(~nanIdx);
hp = hp(~nanIdx);
wt = wt(~nanIdx);

结果1:


背景:

Fuel economy in the U.S. is typically given in miles/gallon. In many countries, however, the standard units are liters/100km.

Given mpg, you can calculate economy in L/100km by dividing 235.214583 by mpg.

任务2:

Create a variable econ that contains the fuel economy in L/100km rather than miles/gallon.

Combine the data for weight, horsepower, and fuel economy in L/100km (in that order) into a 48-by-3 matrix called numdata.

解答2:

Matlab 复制代码
econ = 235.214583./mpg
numdata = [wt hp econ]

笔记:注意mpg是个向量,需要使用"./"。

结果2:


任务3:

Create a matrix of the scatter plots of the variables in numdata (weight, horsepower, and fuel economy) in a single figure.

Calculate the corresponding correlation coefficients and store them as a matrix called cc.

解答3:

Matlab 复制代码
plotmatrix(numdata)
cc = corrcoef(numdata)

结果3:


任务4:

Determine the best-fit line (i.e., a first degree polynomial fit) for fuel economy (in L/100km) as a function of vehicle weight.

Evaluate the fitted model at the weights in the data. Store the fitted values in a vector called econFit.

Note that you do not need to use centering and scaling for the fit.

解答4:

Matlab 复制代码
c = polyfit(wt,econ,1)
econFit = polyval(c,wt)

结果4:


任务5:

Create a scatter plot of fuel economy against weight, and add the best-fit line as a red line.

解答5:

Matlab 复制代码
scatter(wt,econ)
hold on 
plot(wt,econFit,"r")
hold off

结果5:


附加练习:

Try fitting a line to horsepower as a function of weight. Try plotting both scatter plots and fits together, using yyaxis to accommodate the different scales:

附加练习解答:

Matlab 复制代码
chp = polyfit(wt,hp,1)
hpFit = polyval(chp,wt)
yyaxis right
hold on
scatter(wt,hp)
plot(wt,hpFit)
hold off

附加练习结果:

相关推荐
Matlab精灵1 小时前
Matlab科研绘图:自定义内置多款配色函数
算法·matlab
xrgs_shz5 小时前
MATLAB读入不同类型图像并显示图像和相关信息
图像处理·计算机视觉·matlab
火山口车神丶8 小时前
某车企ASW面试笔试题
c++·matlab
今天吃饺子9 小时前
2024年SCI一区最新改进优化算法——四参数自适应生长优化器,MATLAB代码免费获取...
开发语言·算法·matlab
Evand J21 小时前
集合卡尔曼滤波(Ensemble Kalman Filter),用于二维滤波(模拟平面上的目标跟踪),MATLAB代码
matlab·平面·目标跟踪
我是博博啦1 天前
matlab例题
人工智能·算法·matlab
2402_871321951 天前
MATLAB方程组
gpt·学习·线性代数·算法·matlab
Matlab程序猿小助手2 天前
【MATLAB源码-第218期】基于matlab的北方苍鹰优化算法(NGO)无人机三维路径规划,输出做短路径图和适应度曲线.
开发语言·嵌入式硬件·算法·matlab·机器人·无人机
Matlab精灵2 天前
使用MATLAB进行字符串处理
开发语言·matlab
机器学习之心2 天前
POD-Transformer多变量回归预测(Matlab)
matlab·回归·transformer·pod-transformer