MATLAB For Beginners

MATLAB plots 

 plot   Linear plot.
plot(X,Y) plots vector Y versus vector X. If X or Y is a matrix, then the vector is plotted versus the rows or columns of the matrix, whichever line up.  If X is a scalar and Y is a vector, disconnected line objects are created and plotted as discrete points vertically at X.

Various line types, plot symbols and colors may be obtained with plot(X,Y,S) where S is a character string made from one element from any or all the following 3 options:
COLOR: b - blue,    g - green,   r - red,   c - cyan,   m - magenta,  y - yellow,  k - black,   w - white
SYMBOL: . point, o  circle, x   x-mark, +   plus, * star, s square, d diamond, v triangle (down)
LINE TYPE:  - solid, : dotted, -. dashdot, -- dashed, (none) no line
​Example:
x = -pi:pi/10:pi;
       y = tan(sin(x)) - sin(tan(x));
       plot(x,y,'--rs','LineWidth',2,...
                       'MarkerEdgeColor','k',...
                       'MarkerFaceColor','g',...
                       'MarkerSize',10)​

​
\(\color{red}{\diamondsuit}\)Single plot

Script a:
x = 0:0.1:5; 
​\(\color{green}{\text{  % 0.1 spacing creates a smooth curve}}\)
y = x.^2 - 10.*sqrt(x)+2;
​   
    plot (x,y,'b');
    grid;
    xlabel ('x');
    ylabel ('y');
cript b:
x = 0:pi/100:2*pi;
y = sin(x);

  plot (x,y,'r');
​\(\color{green}{\text{  % 'r' creates red color}}\)
  grid;
  xlabel ('x');
  ylabel ('sin(x)  ', 'rotation', 0);

​
\(\color{red}{\clubsuit}\)  Multiple Plots

Script a: 
x = linspace(-2*pi,2*pi);
y1 = sin(x);
y2 = cos(x);
plot(x,y1,x,y2);
script c:
subplot(2,1,1);
x = linspace(0,10);    y1 = sin(x);
subplot(3,1,1);\(\color{green}{\text{  % 3 rows by 1 column, the first row}}\)
plot(x,y1,'r')
subplot(3,1,2);\(\color{green}{\text{  % 3 rows by 1 column, the second row}}\)
y2 = sin(3*x);
plot(x,y2, 'b')
subplot(3,1,3);\(\color{green}{\text{  % 3 rows by 1 column, the third row}}\)
plot(x,y1,'r',x,y2, 'b')
Script b:
'script a' can also be modified as:
x = linspace(-2*pi,2*pi);
y1 = sin(x);
y2 = cos(x);
p1 = plot(x,y1,'linewidth',2 );
grid;
hold on
p2 = plot(x,y2, '*--' );
xlabel('x')
ylabel ('y', 'rotation', 0)
legend ('sin(x)', 'cos(x)', 'location', 'best')
title ('Sine VS Cosine')
hold off
​Script d: 
​'script c' can also be modified as:
subplot(2,1,1);
x = linspace(0,10);      y1 = sin(x);
subplot(2,2,1);
plot(x,y1,'r')
subplot(2,2,2);
y2 = sin(3*x);
plot(x,y2, 'b')
subplot(2,2,[3,4]);\(\color{green}{\text{  % spans the lower half of the figure}}\)
plot(x,y1,'r',x,y2, 'b')
Generate N=100,000 random numbers. Then use the MATLAB “hist” function to plot the results. Depending on the limits set for the ranges of the data for the “hist” function, the histogram plots will be slightly different.
Matlab script:
clear; close all;
N=100000;
R=rand(N,1);
Range =0.0:.1:1.0;
[y,R]=hist(R,Range);
bar(R,y)
grid MINOR
title('SAMPLE HISTOGRAM')
xlabel('Random number R');
ylabel('Number of occurrences')
​Matlab output:
Here is the same script but for a different range.
​
clear; close all;
N=100000;
R=rand(N,1);
Range=0.05:.1:0.95;
[y,R]=hist(R,Range);
bar(R,y)
grid MINOR
title('SAMPLE HISTOGRAM')
xlabel('Random number R');
ylabel('Number of occurrences')
​Matlab output:
Picture
Back to top

PAGE TAGS: AutoCAD, CAD, CATIA, Digital Logic Design, Matlab, VHDL, Links, Programming, Django, Python

Advanced  MatLab applications ​

Latex codes for website​
Matlab script:
​       syms x phi
       latex(x^2 + 1/x)
       latex(sin(pi*x) + phi)
----ans--------------------
ans =
    '\frac{1}{x}+x^2'
ans =
    '\varphi +\sin\left(\pi \,x\right)'
-----------------------------
Use "MatJax" or similar JavaScript platform to generate any math equations.
​
Example:
​Using the above Matlab generated Latex code, you can generate the following expressions in your webpage.

=> \pi +\sin\left(\pi \,x\right)
\(\color{red}{prints:   }\) \(\pi +\sin\left(\pi \,x\right)\)

=>  \varphi +\sin\left(\pi \,x\right)
 \(\color{red}{prints:   }\) \(\varphi +\sin\left(\pi \,x\right)\)

​This is exactly how the math equations are generated in this website.
​