Question

In Matlab, I am trying to figure out how to find and use a acetylene.mat to perform an analysis. In the analysis, I must define independent and dependent variables, create a plot with each dependent variable with each independent variable, given each independent variable and calculate the mean, standard deviation, median, and range of each dependent variable. Finally, I need to give each independent variable plot a boxplot of each dependent variable.

Answer 1

Please find required MATLAB code along with necessary details in comments:

clear all; close all; clc

format short

% acetleyne.mat is an inbuit dataset in MATLAB

load acetylene.mat

data=[x1 x2 x3];

disp('Covariance matrix of the data is given as:')

disp(cov(data));

% Since it is evident that the covariance of x1 and x2 with x3 is very small. So, x3 is assumed to be independednt

% wrt to x1 and x2

% Plots for each dependent variables

subplot(2,1,1)

plot(x1,x2,'r*-');

xlabel('x1'), ylabel('x2');

subplot(2,1,2)

plot(x1,x3,'bo-');

xlabel('x1'), ylabel('x3');

suptitle('For dependent variable wrt to x_1');

% ----------------

figure

subplot(2,1,1)

plot(x2,x3,'r*-');

xlabel('x2'), ylabel('x3');

subplot(2,1,2)

plot(x2,x1,'bo-');

xlabel('x2'), ylabel('x1');

suptitle('For dependent variable wrt to x_2');

% ----------------

figure;

subplot(2,1,1)

plot(x3,x1,'r*-');

xlabel('x3'), ylabel('x1');

subplot(2,1,2)

plot(x3,x2,'bo-');

xlabel('x3'), ylabel('x2');

suptitle('For dependent variable wrt to x_3');

% --------------------------

% calculate mean of each variable

mean_x1=mean(x1)

mean_x2=mean(x2)

mean_x3=mean(x3)

mean_y=mean(y)

% calculate standard deviation of each variable

std_x1=std(x1)

std_x2=std(x2)

std_x3=std(x3)

std_y=std(y)

% calculate meadian of each variable

meadian_x1=median(x1)

meadian_x2=median(x2)

meadian_x3=median(x3)

meadian_y=median(y)

% calculate range of each variable

range_x1=range(x1)

range_x2=range(x2)

range_x3=range(x3)

range_y=range(y)

% draw boxplot for each variable

figure;

subplot(2,2,1)

boxplot(x1);

ylabel('Reactor temperature (degrees centigrade)');

subplot(2,2,2)

boxplot(x2);

ylabel('Rate of H2 to n-heptane (mole ratio)');

subplot(2,2,3)

boxplot(x3);

ylabel('Contact time (seconds)');

subplot(2,2,4)

boxplot(y);

ylabel('Conversion of n-heptane to acetylene (%)');

====================== SCREENSHOT OF CODE

======================= SAMPLE OUTPUT