Sign in to follow this  
Followers 0
E1M1

[Solved]Could someone help me fix my is_prime function?

3 posts in this topic

#1 ·  Posted (edited)

I tried to convert C# conde from wiki to autoit http://en.wikipedia.org/wiki/Trial_division

That's what I got

Func is_prime($number)

if ($number < 2) Then return false;

$d = 2

While ($d * $d <= $number)

$d +=1

if (Mod($number, $d) == 0) Then

return false;

EndIf

WEnd

return true;

EndFunc

This function always returns me true.. for example it returns true for 99, but you can devide 99 with 3, so it's not primenumber. Could someone help me fixing this function pleae?

Edited by E1M1

edited

Share this post


Link to post
Share on other sites



#2 ·  Posted (edited)

E1M1,

I use this function to check primes: :graduated:

For $i = 1 To 100
    If _IsPrime($i) Then ConsoleWrite($i & @CRLF)

Next

Func  _IsPrime($i)

    If $i < 2 Then
        Return False
    ElseIf $i < 4 Then
        Return True
    ElseIf Mod($i, 2) = 0 Then
        Return False
    Else
        $id = 3
        Do
            If Mod($i, $id) = 0 Then Return False
            $id += 2
        Until $id * $id > $i
        Return (($id * $id) > $i)
    EndIf

EndFunc

M23

Edit: See you solved it yourself - would delete post if I could! :(

Edited by Melba23

Any of my own code posted anywhere on the forum is available for use by others without any restriction of any kind._______My UDFs:

Spoiler

ArrayMultiColSort ---- Sort arrays on multiple columns
ChooseFileFolder ---- Single and multiple selections from specified path treeview listing
Date_Time_Convert -- Easily convert date/time formats, including the language used
ExtMsgBox --------- A highly customisable replacement for MsgBox
GUIExtender -------- Extend and retract multiple sections within a GUI
GUIFrame ---------- Subdivide GUIs into many adjustable frames
GUIListViewEx ------- Insert, delete, move, drag, sort, edit and colour ListView items
GUITreeViewEx ------ Check/clear parent and child checkboxes in a TreeView
Marquee ----------- Scrolling tickertape GUIs
NoFocusLines ------- Remove the dotted focus lines from buttons, sliders, radios and checkboxes
Notify ------------- Small notifications on the edge of the display
Scrollbars ----------Automatically sized scrollbars with a single command
StringSize ---------- Automatically size controls to fit text
Toast -------------- Small GUIs which pop out of the notification area

 

Share this post


Link to post
Share on other sites

IsPrime functions can be horribly slow, and including a (not too long) table of initial primes speeds them up tremendously:

:graduated:


Valuater's AutoIt 1-2-3, Class... Is now in Session!For those who want somebody to write the script for them: RentACoder"Any technology distinguishable from magic is insufficiently advanced." -- Geek's corollary to Clarke's law

Share this post


Link to post
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!


Register a new account

Sign in

Already have an account? Sign in here.


Sign In Now
Sign in to follow this  
Followers 0