Raptor

Raptor

1. Visual programming development environment

   • Based on flowcharts

2. Why use it?

   • Minimizes the amount of syntax you must learn
   • Easy of use
   • Error messages easy to understand
   • Doesn´t require a heavy-weight commercial programming language
     • For example
       • C++
       • Java

3. Symbols

   • Start
   • End
   • Loop
   • Call
   • Input
   • Output
   • Selection
   • Processing

4. Variables

   • Only holds a single value
   • The value can change as a program excecutes
   • Ways to set or change a variable
     • By the value entered in an input statement
     • By the value calculated from an ecuation in an assignment statement
     • By a return value from a procedure call
   • Poor variables names
     • Examples
       • a
         • Not descriptive
       • Milesperhour
         • Add underscores
       • My4to
         • Not descriptive
   • Illegal variables names
     • Examples
       • 4sale
         • Doen´t start with a letter
       • Sales tax
         • Includes a space
       • Sales$
         • Includes invalid character
   • Good varible names
     • Examples
       • Tax_rate
       • Sales_tax
       • Distance_in_miles
       • Mpg
   • Common errors
     • "Variable ____ does not have a value"
       • Common reasons
         • The variable has not been given a value
         • The variable name was misspelled
     • "Can't assign string to numeric variable _____" "Can't assign numeric to string variable _____"
       • If the statements attempt to change the data type of a variable.

5. Operations

   • +
     • Addition
   • -
     • Subtraction
     • Negation
   • *
     • Multiplication
   • /
     • Division
   • ^ **
     • Exponentiation, raise a number to a power
   • rem mod
     • Remainder when the right operand divides the left operand
   • sqrt
     • Square root
   • log
     • Natural logarithm (base e)
   • abs
     • Absolute value
   • ceiling
     • Rounds up to a whole number
   • floor
     • Rounds down to a whole number
   • sin
     • trig sin(angle_in_radians)
   • cos
     • trig cos(angle_in_radians)
   • tan
     • trig tan(angle_in_radians)
   • cot
     • trig cotangent(angle_in_radians)
   • arcsin
     • trig sin-1(expression), returns radians
   • arcos
     • trig cos-1(expression), returns radians