#include <Array.au3>

$Nbr_Point = InputBox("Approche polynomiale","Combien de points avez-vous?")

Local $values[$Nbr_Point+1][2]
	$values[0][0] = $Nbr_Point
	$values[0][1] = $Nbr_Point

For $i = 1 To $Nbr_Point
	$x_y =InputBox("Approche polynomiale","Entrez les coordonnées des points sous la forme (x;y)")
	$coor = StringSplit($x_y,";")
	$values[$i][0] = StringRight($coor[1],StringLen($coor[1])-1)
	$values[$i][1] = StringLeft($coor[2],StringLen($coor[2])-1)
Next

;~ _ArrayDisplay($values)

$sum = " 0 "

For $j = 1 To $Nbr_Point
	$sum = $values[$j][1] & _PolynomeNumero($j) & " + " & $sum
Next

MsgBox(0,"Résultat","Le polynome recherché est le suivant ... ")
MsgBox(0,"",StringRegExpReplace($sum,"--","+"))

Func _PolynomeNumero($x)
	Assign("P"&$x,"")
	$P = Eval("P"&$x)
	$delta = 1
	For $i = 1 to $Nbr_Point
	If $i <> $x Then
		$delta = $delta * ( $values[$x][0] - $values[$i][0] )
		$P = $P & "(x-"&$values[$i][0]&")"
;~ 		MsgBox(0,$x,$P)
;~ 		MsgBox(0,"",$delta)
	EndIf

	Next
Return("/("&$delta&") *" & $P)
EndFunc