# génération des 2 courbes cibles Lebbolo

import math
import cmath

fc=1000                       # fréquence caractéristique

inf=20                        # fréquence inférieure
sup=20000                     # fréquence supérieure
N=101                         # nombre de points
offset=90                     # décalage en dB

file_low=open("low_Lebbolo.frd","w")       # nom des fichiers .frd
file_high=open("high_Lebollo.frd","w")

for i in range(0,N):
    
    f=inf*(sup/inf)**(i/(N-1))
    low=(1/(1+1.58*1j*1.17*f/fc-(1.17*f/fc)**2))*1/(1+1j*0.384*f/fc)          # fonctions de transfert
    high=((1j*f/(1.17*fc))**2/(1+1.58*1j*f/(1.17*fc)-(f/(1.17*fc))**2))*1j*f/(0.384*fc)/(1+1j*f/(0.384*fc))
    
    file_low.write(str(f))
    file_low.write("\t")
    file_low.write(str(20*math.log10(abs(low))+offset))
    file_low.write("\t")
    file_low.write(str(57.29*cmath.phase(low)))
    file_low.write("\n")

    file_high.write(str(f))
    file_high.write("\t")
    file_high.write(str(20*math.log10(abs(high))+offset))
    file_high.write("\t")
    file_high.write(str(57.29*cmath.phase(high)))
    file_high.write("\n")
    
file_low.close()
file_high.close()

print('delay tweeter invert :\n',180/fc,'ms\n',18*344/fc,'cm\n',18*135/fc,'in')