Programming Techniques 2.2

Programming Techniques 2.2

1. Data Types

   • Real/Float = Number with a decimal point
   • Integer = Number without decimal point
   • String = A series of characters/TEXT
   • Character = A single letter or symbol
   • Date/Time = Date and time in any format
   • Boolean = Yes no, true false value

2. Errors

   • Syntax error = an error in the rules/grammar of the language Eg missing colon / spelling mistake
   • Logic error = The program is written to do something other than what the programmer intended Eg Resetting only the first 9 elements in an array instead of all 10.
   • Runtime error = More difficult to spot as it can run a program without reporting an error. E.g. runs but Doesn’t give an output. Or the program hangs or Becomes inactive

3. The 3 building blocks of algorithms

   • Selection= controls the flow of an algorithm by checking whether a condition is met or not before determining which steps should follow.
   • Sequence = each step is executed in the order that it is written. All algorithms are made up of at least a basic sequence of instructions.
   • Iteration = controls the flow of an algorithm by repeating a set of instructions either for a fixed number of times or whilst a set condition is met.

4. Operators

   • Arithmetic Operators
     • + Addition eg x=6+5 gives 11
     • - Subtraction eg x=g-5 gives 1
     • * Multiplication eg x=12*2 gives 24
     • / Division eg x= 12/2 gives 6
     • MOD Modulus eg 12MOD5 gives 2
     • DIV Quotient eg 17DIV5 gives 3
     • ^ Exponentiation eg 3^4 gives 81