can’t Multiply Sequence by non-int of type 'float'

Question

Error: can’t Multiply Sequence by non-int of type 'float'

I am facing this error, I know it involves variable types, but I do not know how to make the entry receive a float type value

#TRANSOFORMAÇÃO DE COORDENADAS GEODÉSICAS EM COORDENADAS PLANAS – SISTEMA UTM

from tkinter import *
import math
class SAD69:
    def __init__(self,master):


        frame = Frame(master)
        frame.grid(row=0)
        self.A = 1.0050526248
        self.B = 0.0050632321
        self.C = 10.628107*pow(10,-6)
        self.D = 20.821897*pow(10,-9)
        self.E = 3.9327535*pow(10,-11)
        self.F = 6.5553406*pow(10,-14)
        self.alpha = 111133.3486
        self.delta = 0.021986053
        self.beta =  16.03895511
        self.eps = 3.114475*pow(10,-5)
        self.gama = 16.83348972
        self.x = 4.1531106*pow(10,-8)
        self.pi = 3.141592654
        self.a = 6378160
        self.k = 0.9996
        self.p0 = 57.2957795131
        self.e=0.0066945419
        self.n = 6382845.536
        self. l = 0.0067396609
        self.entry1=Entry(frame)
        self.entry1.grid(row = 4, column =1)
        self.label2 = Label(frame,text='Digite a latitude do ponto >>').grid(row=4,column=0)
        self.entry2=Entry(frame,text='LONGITUDE do ponto')
        self.entry2.grid(row=4, column =3)
        self.label3 =Label(frame,text='Digite a longitude do ponto >>').grid(row=4,column=2)
        self.bt1 =Button(frame,text='Converter',fg='blue',command=self.GEOPLAN)
        self.bt1.grid(row=3, column=1)
    def GEOPLAN(self):
        fia =(self.entry1.get())
        la = (self.entry2.get())
        S = self.a*((1-self.e)*((self.A*(fia*self.pi)/180)-(0.5*self.B*math.sin(2*fia*0.017453292))+(0.25*self.C*math.sin(4*fia*0.017453292))-((1/6)*self.D*math.sin(6*fia*0.017453292))+((1/8)*self.E*math.sin(8*fia*0.017453292))-(0.1*self.F*math.sin(10*fia*0.017453292))))
        I = self.k*self.S
        dl = 3600*(51-la)
        p = dl*0.0001




root = Tk()
root.title='TRANSOFORMAÇÃO DE COORDENADAS GEODÉSICAS EM COORDENADAS PLANAS – SISTEMA UTM'

x=SAD69(root)
root.mainloop()

Answer 1

This error means that a variable containing a sequence (list, tuple, string, etc.) is being multiplied by a float. In Python, if you multiply a sequence by an integer number, it repeats that sequence several times:

>>> [1,2,3] * 4
[1, 2, 3, 1, 2, 3, 1, 2, 3, 1, 2, 3]
>>> (10,20) * 3
(10, 20, 10, 20, 10, 20)
>>> "teste" * 5
'testetestetestetesteteste'

But if you try to multiply by a float, this error occurs:

>>> [1,2,3] * 1.5
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
TypeError: can't multiply sequence by non-int of type 'float'

In his job GEOPLAN the variables fia and la are the result of the Entry.get, which returns the text of a control. The error then occurs because you are trying to multiply this text by a float, without first converting it to a number.

Try converting these two variables into floats before using them:

fia = float(self.entry1.get())
la = float(self.entry2.get())

It can also be interesting to check its format before the conversion, in case the user has entered something that is not a number (I have no experience with Tkinter, so I don’t know whether or not he can do this validation/conversion automatically).