Concepts for MatLab

MATLAB is a high-level programming language primarily used for numerical computing and data analysis. Developed by MathWorks, it provides a powerful environment for matrix manipulation, algorithm development, and visualization. MATLAB's syntax is optimized for mathematical operations, making it particularly suitable for engineers, scientists, and researchers working in fields such as signal processing, image processing, control systems, and machine learning. Key features include built-in functions for linear algebra, statistical analysis, and plotting, as well as an extensive library of toolboxes for specialized applications. MATLAB's interactive environment, combined with its wide range of functionalities, makes it a popular choice for prototyping algorithms and conducting scientific research.

• Print Text

  disp('Hello World!');
  fprintf('Hello World!');

• Comments

  % one line comment
  
  %{
  multi 
  line 
  comment
  %}

• Variables

  carCount = 2;
  name = 'Joe';
  $isPurple = true;

• Data Types

  carCount = 2;
  age = 15;
  seaLevel = -10000;
  usBudget = 11000000000;
  lightSpeed = 11799312874;
  myGPA = 3.45;
  piValue = 3.14159265;
  lastLetter = 'Z';
  isMale = true;
  myName = 'Joe';

• Math Op

  carCount = 6;
  truckCount = 3;
  
  total = carCount + truckCount;
  disp(total);
  
  subtract = carCount - truckCount;
  disp(subtract);
  
  multiple = carCount .* truckCount;
  disp(multiple);
  
  divisble = carCount ./ truckCount;
  disp(divisble);
  
  % performs division and gets remainder which is 0
  modulo = mod(carCount, truckCount);
  disp(modulo);

• Math Functions

  power = 3 .^ 6;
  disp(power);
  
  root = sqrt(16);
  disp(root);
  
  floorVal = floor(3.14);
  disp(floorVal);
  
  ceilVal = ceil(4.3);
  disp(ceilVal);
  
  roundVal = round(3.4);
  disp(roundVal);
  
  % random number from 0 to 100
  ranNum = randi([0, 100]);
  disp(ranNum);
  

• If/Else

  carCount = 6;
  
  if carCount > 3
    display('More than three cars');
  elseif carCount == 3
    display('Equal to three cars');
  else
    display('Less than three cars');
  end

• Ternary

  // No Native Support or Implementation
  

• Switch

  carCount = 3;
  
  switch carCount
    case 1
      disp('One car');
    case 2
      disp('Two cars');
    case 3
      disp('Three cars');
    otherwise
      disp('More than three');
  end

• Functions

  function result = handleCars(cars, wheels)
    result = cars.* wheels;
  end
  
  // command line
  result = handleCars(3, 4)

• Interpolation

  name = "Joe";
  car = "Mazda";
  result = sprintf("%s drives a %s", name, car);
  display(result);

• Type Casting

  function area = squareA(length)
    result = length.^2;
    area = int2str(result);
  end
  
  // command line
  squareL = "4";
  convertedVal = str2num(squareL);
  area = squareA(convertedVal);
  display(area);
  

• Date and Time

  % milliseconds since 1970
  milliseconds = posixtime(datetime('now'));
  disp(milliseconds);
  
  % format current time
  now = datetime;
  disp(now);
  
  % current year
  now.Format = 'yyyy';
  disp(now);
  
  % current month
  now.Format = 'MM';
  disp(now);
  
  % formatted date
  now.Format = "MM/dd/yyyy";
  disp(now);

• Classes

  classdef Cars < handle
    properties
      carList = []
    end
    methods
      function obj = addCar(obj, car)
        obj.carList = [obj.carList , car];
      end
      function obj = removeFirst(obj)
        obj.carList (1) = [];
      end
      function firstCar = getFirstVal(obj)
        firstCar = obj.carList(1);
      end
    end
  end
  
  // command line
  newList = Cars
  newList.addCar("Honda");
  newList.addCar("Mazda");
  newList.addCar("Toyota");
  newList.removeFirst();
  
  firstCar = getFirstVal(newList);
  disp(firstCar);
  

• Inheritance

  classdef User
    properties
      username
      password
    end
  end
  
  classdef Admin < User
    properties
      id
    end
  end
  
  // command line
  newAdmin = Admin;
  newAdmin.id = "1FE";
  newAdmin.username = "alpha0";
  newAdmin.password = "pw1";
  
  disp(newAdmin.username);
  disp(newAdmin.id);
  

• Method Overload

  // No Native Support or Implementation
  

• Abstract Class

  classdef Animation
     methods(Abstract)
        animate_1 = walk(obj);
        animate_2 = run(obj);
        animate_3 = idle(obj);
     end
  end
  
  classdef Human < Animation
    methods
      function walk(obj)
        disp("Human walks");
      end
      function run(obj)
        disp("Human runs");
          end
      function idle(obj)
        disp("Human idles");
      end
    end
  end
  
  classdef Zombie < Animation
    methods
      function walk(obj)
        disp("Zombie walks");
      end
      function run(obj)
        disp("Zombie runs");
          end
      function idle(obj)
        disp("Zombie idles");
      end
    end
  end
  
  player = Human;
  player.walk;
  
  boss1 = Zombie;
  boss1.run;

• Static Class

  classdef Helper
    methods(Static)
      function area = CircleA(radius)
        area = (radius.^2) * 3.14;
      end
      
      function area = SquareA(length)
        area = length.^2;
      end
    end
  end
  
  circle = Helper.CircleA(3);
  disp(circle);
  
  square = Helper.SquareA(4);
  disp(square);

• Arrays/Lists

  names = ["Joe", "Alex", "Bob"];
  names(2) = "Tom";
  name = names(2);
  numItems = size(names);
  
  disp(name);
  disp(numItems);

• Array Methods

  cars = ["Honda", "Mazda", "Toyota"];
  
  % number of elements
  disp(numel(cars));
  
  % checks to see that array is not empty
  disp(isempty(cars));
  
  % last elment of array
  disp(cars(end));
  
  % adds Ford to end of cars
  cars = [cars, "Ford"];
  
  % sorts the array
  cars = sort(cars);
  disp(cars);
  
  % removes the last element
  cars(1)=[];
  disp(cars(numel(cars) - 1));
  
  % remove the first element
  cars(end)=[];
  disp(cars(1));

• Concatenation

  carsListKr = ["Kia", "Hyundai", "Daewoo"];
  carsListJp = ["Honda", "Mazda", "Toyota"];
  combined = horzcat(carsListKr, carsListJp);
  
  disp(combined(2));
  disp(combined(5));
  

• Sort Method

  ages = [5, 3, 1, 6, 7, 4, 19];
  result = sort(ages);
  
  disp(result);

• Objects

  classdef User
    properties
      first;
      last;
      age {mustBeNumeric};
      retired {mustBeNumericOrLogical};
      carBrands;
    end
    methods
      function result = fullName(obj)
        result = sprintf("%s %s", obj.first, obj.last);
      end
    end
  end
  
  // command line
  brands = ["Mazda", "Toyota"];
  user = User ();
  user.first = "Joe";
  user.last = "Doe";
  user.age = 23;
  user.retired = false;
  user.carBrands = brands;
  
  disp(user.first);
  disp(user.carBrands(1));
  disp(user.fullName());

• Maps (Key/Value)

  carMap = dictionary();
  carMap("Joe") = "Toyota";
  carMap("Bob") = "Mazda";
  carMap("Tom") = "Ford";
  
  disp(carMap("Tom"))
  
  carMap = remove(carMap, "Tom");
  disp(isKey(carMap, "Tom"))

• Sets

  # no built in implementation
  # use external libraries
  

• Stack

  cars = [];
  
  cars = [cars, "Mazda"];
  cars = [cars, "Toyota"];
  cars = [cars, "Honda"];
  
  fprintf(cars(end));
  
  cars(end)=[];
  fprintf(cars(end));

• Queues

  cars = [];
  
  cars = [cars, "Mazda"];
  cars = [cars, "Toyota"];
  cars = [cars, "Honda"];
  
  fprintf(cars(1));
  
  cars(1)=[];
  fprintf(cars(1));

• Linked List

  % keep classes in its own files
  
  classdef Node < handle
    properties 
      value 
      next 
    end
    methods
      function obj = Node(Value)
        obj.value = Value;
        obj.next = {};
      end
    end
  end
  
  classdef LinkedList < handle
    properties
      head = {}
    end
    methods
      function obj = add(obj, value)
        newNode = Node(value);
        if isempty(obj.head)
           obj.head = newNode;
        else          
          current = obj.head;
          while isempty(current.next) == 0
            current = current.next;
          end
          current.next = newNode;
        end
      end
  
      function head = returnHead(obj)
        head = obj.head.value;
      end
  
      function traverse(obj)
        current = obj.head;
        while isempty(current) == 0
          disp(current.value);
          current = current.next;
        end
      end
    end
  end
  
  carList = LinkedList();
  obj = carList.add("Mazda");
  obj = carList.add("Toyota");
  obj = carList.add("Honda");
  
  head = carList.returnHead();
  disp(head);
  carList.traverse();

• Graphs

  classdef Graph
    properties
      graphMap
    end
      
    methods
      function obj = Graph()
        obj.graphMap = containers.Map();
      end
          
      function addNode(obj, val)
        obj.graphMap(val) = {};
      end
          
      function addVertices(obj, node1, node2)
        if ~isKey(obj.graphMap, node1)
            obj.graphMap(node1) = {};
        end
        if ~isKey(obj.graphMap, node2)
            obj.graphMap(node2) = {};
        end
  
        obj.graphMap(node1) = [
          obj.graphMap(node1), node2
        ];
        obj.graphMap(node2) = [
          obj.graphMap(node2), node1
        ];
      end
          
      function breadthTraverse(obj, start)
        queue = {start};
        visited = containers.Map(start, true);
        while ~isempty(queue)
          val = queue{1};
          disp(val);
  
          queue(1) = [];
          tempArr = obj.graphMap(val);
          
          for i = 1:length(tempArr)
            if ~visited.isKey(tempArr{i})
              queue = [queue, tempArr{i}];
              visited(tempArr{i}) = true;
            end
          end
        end
      end
  
      function depthTraverse(obj, start)
        stack = {start};
        visited = containers.Map(start, true);
        while ~isempty(stack)
          val = stack{end};
          disp(val);
              
          stack(end) = [];
          tempArr = obj.graphMap(val);
              
          for i = 1:length(tempArr)
            if ~visited.isKey(tempArr{i})
              stack = [stack, tempArr{i}];
              visited(tempArr{i}) = true;
            end
          end
        end
      end
    end
  end
  
  newGraph = Graph();
  newGraph.addNode('a');
  newGraph.addVertices('a', 'b');
  newGraph.addVertices('a', 'c');
  newGraph.addVertices('b', 'd');
  newGraph.addVertices('b', 'e');
  newGraph.addVertices('d', 'f');
  newGraph.addVertices('d', 'g');
  newGraph.addVertices('d', 'h');
  newGraph.addVertices('e', 'i');
  newGraph.addVertices('e', 'j');
  newGraph.breadthTraverse('a');
  newGraph.depthTraverse('a');
  

• For Loops

  names = ["Joe", "Alex", "Bob"];
  
  for i = 1:length(names)
    fprintf(names{i} + "\n");
  end

• While Loops

  carList = ["Mazda", "Toyota", "Honda"];
  
  while size(carList) > 0 
    fprintf(carList(1))
    carList(1)=[];
  end
  
  disp(isempty(carList));

• Loop Breaks

  cars = {"Toyota", "Honda", "Mazda"};
  carCells = cellstr(cars);
  
  for i = 1:length(carCells)
    if carCells(i) == "Honda"
      result = sprintf("Fount at index %d", i);
      fprintf(result);
      break;
    end
  
    result = sprintf("Visited index %d", i);
    fprintf(result);
    fprintf("\n");
  end

• Recursion

  function result = getSum(arr)
    if 1:length(arr) == 1;
      result = arr(1)
    else
      val = arr(1);
      arr(1)=[];
      secVal = getSum(arr)
      result = val + secVal;
    end
  end
  
  testArr = [1, 2, 4, 5];
  result = getSum(testArr);
  
  disp(result);

• Regex Words

  phrase = "I am legend";
  pattern = regexpPattern('[a-zA-Z]+');
  result = extract(phrase, pattern);
  
  % only first result
  disp(result(1));

• Regex Numbers

  phrase = "I am 23";
  pattern = regexpPattern('[0-9]+');
  result = extract(phrase, pattern);
  
  % only first result
  disp(result(1));

• Regex Test

  phrase = "Bob Lee";
  pattern = "Lee";
  result = ~isempty( ...
    regexp(phrase, pattern) ...
  ) && 1;
  
  % only first result
  disp(result);

• Regex Characters

  phrase = "##I am legend##";
  pattern = regexpPattern('\#+[a-zA-Z]');
  result = extract(phrase, pattern);
  
  % only first result
  disp(result(1));