Converting input containing special character to float











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This is the beginning of my program that calculates simple interest. Interest rate will have the following format : 0.97 , 0.67 , 0.17 etc. They won't be bigger than 1. So if the user enter 9 for the interest, program will convert it to 0.09 (by dividing it by 100) . Also user can enter input using '/'. So program will convert input like 97/100 to 0.97.



I wrote the code below. It works but it seems to me that there might be a easier and more elegant solution to this. Maybe using more build-in functions etc. If you help me with that I would be very appreciated.



def toNum(interest):

if '/' not in interest:
if float(interest) > 1:
return float(interest)/100

else:
return float(interest)


else:
l=
n = 0
count = 1

list_interest=
for e in interest:
list_interest.append(e)

for e in list_interest:

if count == 1 or count == 3:
l.append(e)
count = count +1
continue


if e == '/':
n = n + 1
count = count +1
else:
l[n] = l[n] + e

return int(l[0]) / int(l[1])









interest = input("Interest rate: ")
interest = toNum(interest)
print(interest)









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    up vote
    4
    down vote

    favorite












    This is the beginning of my program that calculates simple interest. Interest rate will have the following format : 0.97 , 0.67 , 0.17 etc. They won't be bigger than 1. So if the user enter 9 for the interest, program will convert it to 0.09 (by dividing it by 100) . Also user can enter input using '/'. So program will convert input like 97/100 to 0.97.



    I wrote the code below. It works but it seems to me that there might be a easier and more elegant solution to this. Maybe using more build-in functions etc. If you help me with that I would be very appreciated.



    def toNum(interest):

    if '/' not in interest:
    if float(interest) > 1:
    return float(interest)/100

    else:
    return float(interest)


    else:
    l=
    n = 0
    count = 1

    list_interest=
    for e in interest:
    list_interest.append(e)

    for e in list_interest:

    if count == 1 or count == 3:
    l.append(e)
    count = count +1
    continue


    if e == '/':
    n = n + 1
    count = count +1
    else:
    l[n] = l[n] + e

    return int(l[0]) / int(l[1])









    interest = input("Interest rate: ")
    interest = toNum(interest)
    print(interest)









    share|improve this question







    New contributor




    ikadorus is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
    Check out our Code of Conduct.






















      up vote
      4
      down vote

      favorite









      up vote
      4
      down vote

      favorite











      This is the beginning of my program that calculates simple interest. Interest rate will have the following format : 0.97 , 0.67 , 0.17 etc. They won't be bigger than 1. So if the user enter 9 for the interest, program will convert it to 0.09 (by dividing it by 100) . Also user can enter input using '/'. So program will convert input like 97/100 to 0.97.



      I wrote the code below. It works but it seems to me that there might be a easier and more elegant solution to this. Maybe using more build-in functions etc. If you help me with that I would be very appreciated.



      def toNum(interest):

      if '/' not in interest:
      if float(interest) > 1:
      return float(interest)/100

      else:
      return float(interest)


      else:
      l=
      n = 0
      count = 1

      list_interest=
      for e in interest:
      list_interest.append(e)

      for e in list_interest:

      if count == 1 or count == 3:
      l.append(e)
      count = count +1
      continue


      if e == '/':
      n = n + 1
      count = count +1
      else:
      l[n] = l[n] + e

      return int(l[0]) / int(l[1])









      interest = input("Interest rate: ")
      interest = toNum(interest)
      print(interest)









      share|improve this question







      New contributor




      ikadorus is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
      Check out our Code of Conduct.











      This is the beginning of my program that calculates simple interest. Interest rate will have the following format : 0.97 , 0.67 , 0.17 etc. They won't be bigger than 1. So if the user enter 9 for the interest, program will convert it to 0.09 (by dividing it by 100) . Also user can enter input using '/'. So program will convert input like 97/100 to 0.97.



      I wrote the code below. It works but it seems to me that there might be a easier and more elegant solution to this. Maybe using more build-in functions etc. If you help me with that I would be very appreciated.



      def toNum(interest):

      if '/' not in interest:
      if float(interest) > 1:
      return float(interest)/100

      else:
      return float(interest)


      else:
      l=
      n = 0
      count = 1

      list_interest=
      for e in interest:
      list_interest.append(e)

      for e in list_interest:

      if count == 1 or count == 3:
      l.append(e)
      count = count +1
      continue


      if e == '/':
      n = n + 1
      count = count +1
      else:
      l[n] = l[n] + e

      return int(l[0]) / int(l[1])









      interest = input("Interest rate: ")
      interest = toNum(interest)
      print(interest)






      python python-3.x






      share|improve this question







      New contributor




      ikadorus is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
      Check out our Code of Conduct.











      share|improve this question







      New contributor




      ikadorus is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
      Check out our Code of Conduct.









      share|improve this question




      share|improve this question






      New contributor




      ikadorus is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
      Check out our Code of Conduct.









      asked Nov 26 at 13:51









      ikadorus

      234




      234




      New contributor




      ikadorus is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
      Check out our Code of Conduct.





      New contributor





      ikadorus is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
      Check out our Code of Conduct.






      ikadorus is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
      Check out our Code of Conduct.






















          2 Answers
          2






          active

          oldest

          votes

















          up vote
          4
          down vote



          accepted










          For reading a fraction such as "97/100", you can use the fractions library.



          For example:





          from fractions import Fraction

          f = Fraction("97/100")

          print(float(f)) # prints 0.97


          And because the constructor also takes a float, we can remove the check for /. Therefore, the final code is:



          from fractions import Fraction

          def toNum(interest):
          f = Fraction(interest)
          f = float(f)

          if f > 1:
          f /= 100

          return f

          print(toNum("97/100")) # prints 0.97
          print(toNum(0.97)) # prints 0.97
          print(toNum(9)) # prints 0.09





          share|improve this answer



















          • 1




            Why convert to float at all and not keep a fractions.Fraction object all along?
            – Mathias Ettinger
            Nov 26 at 15:59










          • @MathiasEttinger That's also a good option, just depends on preference.
            – esote
            Nov 26 at 16:14


















          up vote
          1
          down vote













          While the answer by @esote is correct and I would also recommend using the fractions module, you should also work on your text parsing. In this case you could have used a simple str.split and map to parse the string containing a /:



          if "/" in interest:
          numerator, denominator = map(int, interest.split("/"))
          return numerator / denominator


          Note that int ignores whitespace, so this works with both "97/100", "97 / 100" and any combination thereof.



          Note also that using sensible names makes it immediately obvious what this code does.






          share|improve this answer





















            Your Answer





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            2 Answers
            2






            active

            oldest

            votes








            2 Answers
            2






            active

            oldest

            votes









            active

            oldest

            votes






            active

            oldest

            votes








            up vote
            4
            down vote



            accepted










            For reading a fraction such as "97/100", you can use the fractions library.



            For example:





            from fractions import Fraction

            f = Fraction("97/100")

            print(float(f)) # prints 0.97


            And because the constructor also takes a float, we can remove the check for /. Therefore, the final code is:



            from fractions import Fraction

            def toNum(interest):
            f = Fraction(interest)
            f = float(f)

            if f > 1:
            f /= 100

            return f

            print(toNum("97/100")) # prints 0.97
            print(toNum(0.97)) # prints 0.97
            print(toNum(9)) # prints 0.09





            share|improve this answer



















            • 1




              Why convert to float at all and not keep a fractions.Fraction object all along?
              – Mathias Ettinger
              Nov 26 at 15:59










            • @MathiasEttinger That's also a good option, just depends on preference.
              – esote
              Nov 26 at 16:14















            up vote
            4
            down vote



            accepted










            For reading a fraction such as "97/100", you can use the fractions library.



            For example:





            from fractions import Fraction

            f = Fraction("97/100")

            print(float(f)) # prints 0.97


            And because the constructor also takes a float, we can remove the check for /. Therefore, the final code is:



            from fractions import Fraction

            def toNum(interest):
            f = Fraction(interest)
            f = float(f)

            if f > 1:
            f /= 100

            return f

            print(toNum("97/100")) # prints 0.97
            print(toNum(0.97)) # prints 0.97
            print(toNum(9)) # prints 0.09





            share|improve this answer



















            • 1




              Why convert to float at all and not keep a fractions.Fraction object all along?
              – Mathias Ettinger
              Nov 26 at 15:59










            • @MathiasEttinger That's also a good option, just depends on preference.
              – esote
              Nov 26 at 16:14













            up vote
            4
            down vote



            accepted







            up vote
            4
            down vote



            accepted






            For reading a fraction such as "97/100", you can use the fractions library.



            For example:





            from fractions import Fraction

            f = Fraction("97/100")

            print(float(f)) # prints 0.97


            And because the constructor also takes a float, we can remove the check for /. Therefore, the final code is:



            from fractions import Fraction

            def toNum(interest):
            f = Fraction(interest)
            f = float(f)

            if f > 1:
            f /= 100

            return f

            print(toNum("97/100")) # prints 0.97
            print(toNum(0.97)) # prints 0.97
            print(toNum(9)) # prints 0.09





            share|improve this answer














            For reading a fraction such as "97/100", you can use the fractions library.



            For example:





            from fractions import Fraction

            f = Fraction("97/100")

            print(float(f)) # prints 0.97


            And because the constructor also takes a float, we can remove the check for /. Therefore, the final code is:



            from fractions import Fraction

            def toNum(interest):
            f = Fraction(interest)
            f = float(f)

            if f > 1:
            f /= 100

            return f

            print(toNum("97/100")) # prints 0.97
            print(toNum(0.97)) # prints 0.97
            print(toNum(9)) # prints 0.09






            share|improve this answer














            share|improve this answer



            share|improve this answer








            edited Nov 26 at 15:03

























            answered Nov 26 at 14:11









            esote

            1,4151731




            1,4151731








            • 1




              Why convert to float at all and not keep a fractions.Fraction object all along?
              – Mathias Ettinger
              Nov 26 at 15:59










            • @MathiasEttinger That's also a good option, just depends on preference.
              – esote
              Nov 26 at 16:14














            • 1




              Why convert to float at all and not keep a fractions.Fraction object all along?
              – Mathias Ettinger
              Nov 26 at 15:59










            • @MathiasEttinger That's also a good option, just depends on preference.
              – esote
              Nov 26 at 16:14








            1




            1




            Why convert to float at all and not keep a fractions.Fraction object all along?
            – Mathias Ettinger
            Nov 26 at 15:59




            Why convert to float at all and not keep a fractions.Fraction object all along?
            – Mathias Ettinger
            Nov 26 at 15:59












            @MathiasEttinger That's also a good option, just depends on preference.
            – esote
            Nov 26 at 16:14




            @MathiasEttinger That's also a good option, just depends on preference.
            – esote
            Nov 26 at 16:14












            up vote
            1
            down vote













            While the answer by @esote is correct and I would also recommend using the fractions module, you should also work on your text parsing. In this case you could have used a simple str.split and map to parse the string containing a /:



            if "/" in interest:
            numerator, denominator = map(int, interest.split("/"))
            return numerator / denominator


            Note that int ignores whitespace, so this works with both "97/100", "97 / 100" and any combination thereof.



            Note also that using sensible names makes it immediately obvious what this code does.






            share|improve this answer

























              up vote
              1
              down vote













              While the answer by @esote is correct and I would also recommend using the fractions module, you should also work on your text parsing. In this case you could have used a simple str.split and map to parse the string containing a /:



              if "/" in interest:
              numerator, denominator = map(int, interest.split("/"))
              return numerator / denominator


              Note that int ignores whitespace, so this works with both "97/100", "97 / 100" and any combination thereof.



              Note also that using sensible names makes it immediately obvious what this code does.






              share|improve this answer























                up vote
                1
                down vote










                up vote
                1
                down vote









                While the answer by @esote is correct and I would also recommend using the fractions module, you should also work on your text parsing. In this case you could have used a simple str.split and map to parse the string containing a /:



                if "/" in interest:
                numerator, denominator = map(int, interest.split("/"))
                return numerator / denominator


                Note that int ignores whitespace, so this works with both "97/100", "97 / 100" and any combination thereof.



                Note also that using sensible names makes it immediately obvious what this code does.






                share|improve this answer












                While the answer by @esote is correct and I would also recommend using the fractions module, you should also work on your text parsing. In this case you could have used a simple str.split and map to parse the string containing a /:



                if "/" in interest:
                numerator, denominator = map(int, interest.split("/"))
                return numerator / denominator


                Note that int ignores whitespace, so this works with both "97/100", "97 / 100" and any combination thereof.



                Note also that using sensible names makes it immediately obvious what this code does.







                share|improve this answer












                share|improve this answer



                share|improve this answer










                answered Nov 27 at 11:27









                Graipher

                22.5k53384




                22.5k53384






















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