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September 06, 2004
A Simple Macro: Fibonacci Numbers
When learning a new (computer) language - it is important to have a good mastery of the basics. Developing simple functions like this is what is called for here.
Function Fibonacci(Val As Integer) As Long
Dim I As Integer
Fibonacci = 1
For I = 1 To Val
Fibonacci = Fibonacci * I
Next I
End Function
We can now call our newly created function from the spreadsheet - just like the builtin OOo Calc functions.
Posted by Dave at September 6, 2004 04:34 AM
Comments
I hate to be pedantic (actually, no. I love it).
However, your Fibonacci number macro doesn't return Fibonacci numbers, it returns factorials.
A factorial is represented by the symbol !, and is the product of an integer and every natural number preceeding it (0 and negative numbers aren't natural numbers). So 1! = 1, 2! = 2, 3!=6 etc
A Fibonacci sequence is one where Un+2=Un+1+Un
The most common quoted Fibonacci sequence goes 1,1,2,3,5,8,13,21,34,55 etc...
Otherwise, keep up the good work!
Posted by: Tim Clarke at February 25, 2005 08:23 PM
These are not Fibonacci numbers; they are the factorials. Fibonacci numbers are generated like this:
fib(1) = fib(2) = 1
for n > 2, fib(n) = fib(n-1) + fib(n-2)
Posted by: Ed Martin at February 25, 2005 10:52 PM
¿What about 0,1,1,2,3,5,8,13,21,34,55?
Function Fibonacci(Val As Integer) As Long
Dim I As Integer
Fibonacci = 1
For I = 0 To Val-2
Fibonacci = Fibonacci + I
Next I
Fibonacci = Fibonacci + 1
End Function
Posted by: Jonatan de la Torre at July 12, 2005 06:12 AM
This is how I'd make Fibonacci function for calc.
It does work fine.
REM ***** BASIC *****
REM ***** Fibonacci *****
REM ***** Cálcula el numero fibonacci de orden Val ***
Function fib(byval Val As Integer) As Double
Dim I As Integer
Dim fib2 As Double
Dim fib1 As Double
fib = 0
fib2 = 0
fib1 = 1
If Val < 2 Then
IIf (Val = 0, fib = fib2 , fib = fib1)
Goto Fin
End If
For I = 2 To Val
fib = fib2 + fib1
fib2 = fib1
fib1 = fib
Next I
Fin:
End Function
Posted by: Jonatan de la Torre at July 20, 2005 08:51 AM