Download Solution LAB 1: Introduction to the MATLAB environment

CIVE 3066: Engineering systems and decision analysis
Fall 2016 (55NKN)
Solution LAB 1: Introduction to the MATLAB environment
Exercice 1: Create x is a row vector containing 10 double random numbers whose value is
between 3 and 10.
x=3 + (10-3)*rand(1,10,’double’);
Exercice 2: Create the following matrices:
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A is a matrix with 2 rows and 3 three columns containing double random numbers whose
value is between 10 and 15.
A=10 + (15-10)*rand(2,3,’double’);
B is a diagonal matrix of size 2x2 with the random value in the principal diagonal.
% V is a vector containing 2 random values
V=rand(1,2);
% B is the diagonal matrix with the random values of V in the principal diagonal
B=diag(V);
C is a matrix of size 5x5 with the random values in the second diagonal
% V is a vector containing 5 random values
V=rand(1,5);
% C is the diagonal matrix with the random values of V in the principal diagonal
C=diag(V);
% inverse the column of C so that the values in the principal diagonal are moved to the second diagonal
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C=C(:,end:-1:1);
D is a matrix with 7 rows and 5 columns which is created by concatenating the matrices
A and B in the two first rows and the matrix C in the five last row as the following matrix
(A(i,j) represent the value of the matrices A at row i and column j, and so on):
A(1,1) A(1,2) A(1,3) B(1,1) B(1,2)
A(2,1) A(2,2) A(2,3) B(2,1) B(2,2)
C(1,1) C(1,2) C(1,3) C(1,4) C(1,5)
C(2,1) C(2,2) C(2,3) C(2,4) C(2,5)
C(3,1) C(3,2) C(3,3) C(3,4) C(3,5)
C(4,1) C(4,2) C(4,3) C(4,4) C(4,5)
C(5,1) C(5,2) C(5,3) C(5,4) C(5,5)
D=[A B; C];
E is a sub matrix of size 6x2 which takes the values in the rows from 1 to 3 and from 5 to
7 and in the columns 2 and 4 of the matrix D.
E=D([1:3 5:7], [2 4]);
Exercise 3:
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Create a vector x of 10 abscissa values linearly spaced between 0 and Pi.
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CIVE 3066: Engineering systems and decision analysis
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Fall 2016 (55NKN)
x=linspace(0, pi,10);
Create three vectors of the values taken by the functions sinus, arctangent and square
on the values of the abscissa vector.
y1=sin(x);
y2=atan(x);
y3=x.^2;
Plot the curves of functions sinus, arctangent and square between 0 and Pi.
p=plot(x,y1,x,y2,x,y3)
Improve the previous plot by adding the title “Plot of sin, square and arctangent
functions by your name”. (put your name in the title (VD: Nguyen Van A))
title 'Plot of sin, square and arctangent function by Nguyen Van A';
Add a label for the abscissa ‘x’ and for the ordinate ‘y’
xlabel 'x';
ylabel 'y';
Use ‘*’ markers and solid line for the curve of the square
set(p(3),'LineStyle' , '-', 'Marker', '*');
Use a dashed line style for the curve of the arctangent
set(p(2),'LineStyle' , '--');
Use dotted line, magenta color and square markers for the curve of the sinus
set(p(1),'LineStyle' , ':', 'Color', 'm', 'Marker', 's');
Add legend for the three curves above
legend('sin(x)','atan(x)','x^2');
Limit the plot to the ordinates between 0 and 6 for y and 0 to pi for x.
axis([0 pi 0 6]);
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