Programming

Programming

1. Algorithm

   • Solving problems 1 step at a time
   • Processors can only process 1 instructions at a time
   • Mainly expressed as a flow chart
     • Make sure you know the symbols

2. High level / low level programming

   • High level has to be translated
     • eg Python, BASIC, Javascript
   • Low level is understood by the processor
     • Assembly language
       • Codes specefic to a type of processor
       • eg INP, LDA, OUT
       • Written as each instruction would be a processed
     • Machine code
       • binary codes for each instruction and register location

3. Testing

   • Logical error
     • Human error with the construction of the algorithm
   • Run-time error
     • An error in the program eg stuck in a loop
   • Syntax error
     • Not a correct command for the coding language being used

4. Data type

   • Variable or constant
     • Variable changes during the program eg score in a game
     • Constant stays the same eg Pi
   • Operations are mathematical symbols eg <>+-
   • Arrays are lists of the same data types
   • Integers and real numbers
     • Real (sometimes called float) can have decimal places
     • Integer is a whole number

5. Pseudocode

   • Used for planning algorithms
   • Should allow a programmer to write it in any language
   • Key words written in capital letters (eg INPUT, IF, WHILE)

6. Translation

   • Interpreter
     • Used when creating a program
     • Would be used on open source software
     • Executes the source code directly
   • Compiler
     • Creates an executable file to run the programming
     • Once it is compiled doesn't need the original source code
     • Would be used for proprietary software
   • Assembler
     • Turns assembly language into machine code
     • Only can be used in low level programming

7. Control Flow

   • Sequencing
     • The order through an alogrithm
   • Selection
     • IF THEN ELSE
   • iteration
     • Loops
       • WHILE or FOR