I've been trying to get a fix and can't find why the error keeps appearing. Pmin,Pmax,w,fi1 and fi2 have all been assigned finite values

guess=Pmin+(Pmax-Pmin)*((1-w**2)*fi1+(w**2)*fi2)

When i remove this line from the code, the same error appears at the next line of code, again for no reason I can think of

Edit: Here is the chunk of code I was referring to:

def Psat(self, T):
pop= self.getPborder(T)
boolean=int(pop[0])
P1=pop[1]
P2=pop[2]
if boolean:
Pmin = float(min([P1, P2]))
Pmax = float(max([P1, P2]))
Tr=T/self.typeMolecule.Tc
w=0.5*(1+scipy.tanh((10**5)*(Tr-0.6))) fi1=0.5*(1-scipy.tanh(8*((Tr**0.4)-1)))

fi2=0.460*scipy.sqrt(1-(Tr-0.566)**2/(0.434**2)+0.494
guess = Pmin+(Pmax-Pmin)*((1-w**2)*fi1+(w**2)*fi2)
#error here

solution = scipy.optimize.newton(funcPsat,guess, args=(T,self))