Polynome du second degrès

polynomeduseconddegrs.py

from math import *
from kandinsky import *
for i in range(12) : print("")
print("  --------------------------")
print("Etude d'un polynome ax^2+bx+c")
print("  --------------------------")
print("")
a=0
# Demande des coefficients du trinome
while a==0 : a=float(input('Valeur de a ? '))
b=float(input('Valeur de b ? '))
c=float(input('Valeur de c ?'))
for i in range(12) : print("")

delta=b**2-4*a*c
print("Forme developpe = {}x^2+{}x+{}".format(a, b, c))
print("Delta = {}**2-4{}*{}".format(b, a, c))
print("Delta = {}".format(delta))
# calcul de delta, alpha et beta
alpha=-b/(2*a)
beta=-delta/(4*a)
#Affichage du texte selon
#les coefficients a, b et c
if delta == 0 :
  print("Delta = 0")
  print("Le trinome admet pour")
  print("racine : x0=-b/(2a)")
  x0=-b/(2*a)
  print("  x0 = ",x0)
  print("Sommet de la parabole :")
  print("  S(",x0,",0)")
elif delta > 0 :
  print("Delta = ",delta," > 0 donc les")
  print("racines de ce trinome sont :")
  x1=(-b-sqrt(delta))/(2*a)
  x2=(-b+sqrt(delta))/(2*a)
  print("  x1 = ",x1," et x2 = ",x2)
  print("Sommet de la parabole :")
  print("  S(",alpha,",",beta,")")
  print("Forme factorisee du trinome :")
  print(" ",a,"(x+",-x1,")(x+",-x2,")")
else :
  print ("Delta = ",delta)
  print("donc le trinome n'admet")
  print("pas de racines reelles")
  print("Sommet de la parabole :")
  print("  S(",alpha,",",beta,")")
print("Forme canonique du trinome :")
print(" ",a,"(x+",-alpha,")^2 +",+beta)
#Affichage de la parabole du trinome
choix=input('Tracer la courbe ? [o/n]')
if choix=='n' or choix=='8':
  print("       - - - FIN - - -")
else : ## Partie pour tracer le graphique vous n'êtes pas obliger de la comprendre
  Xmin,Xmax,Ymin,Ymax=-10,10,-10,10
  red=color(255,0,0)
  black=color(0,0,0)
  for pixel_x in range(320):
    X=Xmin+pixel_x*(Xmax-Xmin)/319
    Y=a*X**2+b*X+c
    pixel_y=int((Y-Ymax)*221/(Ymin-Ymax))
    set_pixel(pixel_x,pixel_y,red)
  for x in range(320):
    y_0=int(Ymax*221/(Ymax-Ymin))
    set_pixel(x,y_0,black)
  for y in range(222):
    x_0=int(Xmin*319/(Xmin-Xmax))
    set_pixel(x_0,y,black)