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Remove email addresses

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Boris Verkhovskiy
2024-05-31 12:18:45 -06:00
parent 37f0b26450
commit 3ea2b0b29f
13 changed files with 381 additions and 437 deletions
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@@ -10,10 +10,6 @@ contributors:
MATLAB stands for MATrix LABoratory. It is a powerful numerical computing language commonly used in engineering and mathematics.
If you have any feedback please feel free to reach me at
[@the_ozzinator](https://twitter.com/the_ozzinator), or
[osvaldo.t.mendoza@gmail.com](mailto:osvaldo.t.mendoza@gmail.com).
```matlab
%% Code sections start with two percent signs. Section titles go on the same line.
% Comments start with a percent sign.
@@ -49,42 +45,42 @@ plot(A);
% commands can be passed to the operating system
!ping google.com
who % Displays all variables in memory
whos % Displays all variables in memory, with their types
clear % Erases all your variables from memory
clear('A') % Erases a particular variable
who % Displays all variables in memory
whos % Displays all variables in memory, with their types
clear % Erases all your variables from memory
clear('A') % Erases a particular variable
openvar('A') % Open variable in variable editor
clc % Erases the writing on your Command Window
diary % Toggle writing Command Window text to file
clc % Erases the writing on your Command Window
diary % Toggle writing Command Window text to file
ctrl-c % Abort current computation
edit('myfunction.m') % Open function/script in editor
type('myfunction.m') % Print the source of function/script to Command Window
profile on % turns on the code profiler
profile off % turns off the code profiler
profile viewer % Open profiler
profile on % turns on the code profiler
profile off % turns off the code profiler
profile viewer % Open profiler
help command % Displays documentation for command in Command Window
doc command % Displays documentation for command in Help Window
lookfor command % Searches for command in the first commented line of all functions
help command % Displays documentation for command in Command Window
doc command % Displays documentation for command in Help Window
lookfor command % Searches for command in the first commented line of all functions
lookfor command -all % searches for command in all functions
% Output formatting
format short % 4 decimals in a floating number
format long % 15 decimals
format bank % only two digits after decimal point - for financial calculations
format short % 4 decimals in a floating number
format long % 15 decimals
format bank % only two digits after decimal point - for financial calculations
fprintf('text') % print "text" to the screen
disp('text') % print "text" to the screen
disp('text') % print "text" to the screen
% Variables & Expressions
myVariable = 4 % Notice Workspace pane shows newly created variable
myVariable = 4 % Notice Workspace pane shows newly created variable
myVariable = 4; % Semi colon suppresses output to the Command Window
4 + 6 % ans = 10
8 * myVariable % ans = 32
2 ^ 3 % ans = 8
4 + 6 % ans = 10
8 * myVariable % ans = 32
2 ^ 3 % ans = 8
a = 2; b = 3;
c = exp(a)*sin(pi/2) % c = 7.3891
@@ -92,7 +88,7 @@ c = exp(a)*sin(pi/2) % c = 7.3891
% Standard function syntax:
load('myFile.mat', 'y') % arguments within parentheses, separated by commas
% Command syntax:
load myFile.mat y % no parentheses, and spaces instead of commas
load myFile.mat y % no parentheses, and spaces instead of commas
% Note the lack of quote marks in command form: inputs are always passed as
% literal text - cannot pass variable values. Also, can't receive output:
[V,D] = eig(A); % this has no equivalent in command form
@@ -338,8 +334,8 @@ load('myFileName.mat') % Load saved variables into Workspace
% Function name should match file name (so save this example as double_input.m).
% 'help double_input.m' returns the comments under line beginning function
function output = double_input(x)
%double_input(x) returns twice the value of x
output = 2*x;
%double_input(x) returns twice the value of x
output = 2*x;
end
double_input(6) % ans = 12
@@ -375,23 +371,23 @@ fprintf % Print to Command Window with more control
% Conditional statements (the parentheses are optional, but good style)
if (a > 23)
disp('Greater than 23')
disp('Greater than 23')
elseif (a == 23)
disp('a is 23')
disp('a is 23')
else
disp('neither condition met')
disp('neither condition met')
end
% Looping
% NB. looping over elements of a vector/matrix is slow!
% Where possible, use functions that act on whole vector/matrix at once
for k = 1:5
disp(k)
disp(k)
end
k = 0;
while (k < 5)
k = k + 1;
k = k + 1;
end
% Timing code execution: 'toc' prints the time since 'tic' was called
@@ -435,11 +431,11 @@ randi % Uniformly distributed pseudorandom integers
randn % Normally distributed pseudorandom numbers
%Complex math operations
abs(x) % Magnitude of complex variable x
abs(x) % Magnitude of complex variable x
phase(x) % Phase (or angle) of complex variable x
real(x) % Returns the real part of x (i.e returns a if x = a +jb)
imag(x) % Returns the imaginary part of x (i.e returns b if x = a+jb)
conj(x) % Returns the complex conjugate
conj(x) % Returns the complex conjugate
% Common constants
@@ -496,23 +492,23 @@ median % median value
mean % mean value
std % standard deviation
perms(x) % list all permutations of elements of x
find(x) % Finds all non-zero elements of x and returns their indexes, can use comparison operators,
find(x) % Finds all non-zero elements of x and returns their indexes, can use comparison operators,
% i.e. find( x == 3 ) returns indexes of elements that are equal to 3
% i.e. find( x >= 3 ) returns indexes of elements greater than or equal to 3
% Classes
% MATLAB can support object-oriented programming.
% Classes must be put in a file of the class name with a .m extension.
% MATLAB can support object-oriented programming.
% Classes must be put in a file of the class name with a .m extension.
% To begin, we create a simple class to store GPS waypoints.
% Begin WaypointClass.m
classdef WaypointClass % The class name.
properties % The properties of the class behave like Structures
latitude
longitude
latitude
longitude
end
methods
% This method that has the same name of the class is the constructor.
methods
% This method that has the same name of the class is the constructor.
function obj = WaypointClass(lat, lon)
obj.latitude = lat;
obj.longitude = lon;
@@ -543,12 +539,12 @@ a.longitude = 25.0
% Methods can be called in the same way as functions
ans = multiplyLatBy(a,3)
% The method can also be called using dot notation. In this case, the object
% The method can also be called using dot notation. In this case, the object
% does not need to be passed to the method.
ans = a.multiplyLatBy(1/3)
% MATLAB functions can be overloaded to handle objects.
% In the method above, we have overloaded how MATLAB handles
% MATLAB functions can be overloaded to handle objects.
% In the method above, we have overloaded how MATLAB handles
% the addition of two Waypoint objects.
b = WaypointClass(15.0, 32.0)
c = a + b
@@ -560,4 +556,3 @@ c = a + b
* [The official MATLAB Answers forum](http://www.mathworks.com/matlabcentral/answers/)
* [Loren on the Art of MATLAB](http://blogs.mathworks.com/loren/)
* [Cleve's Corner](http://blogs.mathworks.com/cleve/)