Programming Basics

Programming Basics

1. Data Types

   • Integer - Whole numbers e.g 200.
   • Real - Numbers that have a decimal point e.g. 7.9
   • Boolean - Can only take one of two values e.g. true or false
   • Character - A single letter, number or symbol e.g. A, 5
   • String - Used to represent text, it is a collection of characters e.g. T5d8D
   • Casting - Lanuages have functions that let you manually convert between data types and thgis is known as casting. Which can be done using commands like int(), float(), bool() and str() commands.

2. Operators

   • The arithmetic operators take two values and perform a math function.
   • == - is equal to. != is not equal to. < is less then. > is greater then. <= is less then or equal to. >= is greater then or equal to

3. Strings

   • Strings are usually written inside double quotation marks but can also be in single ones. Strings can be joined together this is called concatenation and is done by using the + symbol.
   • x.upper changes all characters to upper case, x.lower changes all characters to lower case and x.length returns the number of characters in string.x

4. Program Flow

   • IF statements allow you to check if a condition is true or false, and carry out different actions depending on the outcome. You can think about them as a flow diagram.
   • Nested IF statement - Can be made by putting one IF statement inside another one. Nested IF statements allow you to check more conditions once you have established the previous condition is true.
   • IF ELSEIF statements can also be used to check multiple conditions. They are different from nested IF statements as they only check more conditions if the previous one is true.
   • SWITCH CASE statements can check if a variable has specific values.. The drawback is they can only check the value of one variable.

5. Loops

   • Repeat loops are controlled by a condition at the end, keeps going until it is true, always runs the code inside it at least once and you get infinite loop if the condition is never true.
   • While loops are controlled by a condition at the start of the loop, keeps going until it is true, never runs the code if initially false and you get an infinite loop if the condition is always true.
   • Do while loops controlled by a condition at the end of the loop, keeps going while it's true, always runs code inside at least once and you get an infinite loop if the condition is always true.

6. Arrays

   • An array is a data structure that can store a collection of data values all under one name. Each piece of data in an array is called an element. Arrays are most helpful when you have lots of related data you want to store and it does not make sense to use separate variable.