Datetime module - ValueError try/except won't work python 3

-2

I have a programming homework assignment. Everything went smoothly until I reached a problem using Try/Except. If I type a valid datetime, the program will take it and it will move on, but if I use a valid datetime format, the exception won't react.

Here is my code:

 import datetime

import csv





def get_stock_name(prompt,mode):

    while True:

        try:

            return open(input(prompt) + ".csv")

        except FileNotFoundError:

            print("File not found. Please try again.")

        except IOError:

            print("There was an IOError opening the file. Please try again.")





def get_stock_date(prompt):

    while True:

        try:

            return (input(prompt))

        except TypeError:

            print("Try again.")

        except ValueError:

            print("Try again.")





def get_stock_purchased(prompt):

    while True:

        try:

            return (input(prompt))

        except ValueError:

            print("Try again.")

        except TypeError:

            print("try again.")





stock_name = get_stock_name("Enter the name of the file ==> ", "w")



stock_date = datetime.datetime.strptime(get_stock_date("Enter the stock purchase date ==> " , "%m/%d/%Y"))



stock_sold = datetime.datetime.strptime(get_stock_date("Enter the date you sold the stock ==>" , "%m/%d/%Y"))



stock_purchased = get_stock_purchased("How many stocks were purchased on start date ==>")

edited Apr 11 '16 at 4:38

asked Apr 11 '16 at 4:22

tokyolerd

227

How could there be a TypeError or ValueError if all you're doing is input()? And if it succeeds, it stops the function. I think you need to have another look at while, return, and possibly break. Oh, and also at recursion. And saving references.

– TigerhawkT3
Apr 11 '16 at 4:26

The exception is raised in python 2? What do you input?

– tdelaney
Apr 11 '16 at 4:28

@TigerhawkT3 Thanks! And while I was messing around with it, it gave me two different errors (TypeError and ValueError) So that's why I made two exceptions.

– tokyolerd
Apr 11 '16 at 4:30

@tdelaney Python 3. If I input 5/10/2004 it will move on, but if I input anything else, It will give me a ValueError.

– tokyolerd
Apr 11 '16 at 4:31

Also, your parens are messed up - you're sending two arguments to the recursive call of get_stock_date and only one to strptime.

– TigerhawkT3
Apr 11 '16 at 4:32

|
show 4 more comments

-2

Here is my code:

 import datetime

import csv





def get_stock_name(prompt,mode):

    while True:

        try:

            return open(input(prompt) + ".csv")

        except FileNotFoundError:

            print("File not found. Please try again.")

        except IOError:

            print("There was an IOError opening the file. Please try again.")





def get_stock_date(prompt):

    while True:

        try:

            return (input(prompt))

        except TypeError:

            print("Try again.")

        except ValueError:

            print("Try again.")





def get_stock_purchased(prompt):

    while True:

        try:

            return (input(prompt))

        except ValueError:

            print("Try again.")

        except TypeError:

            print("try again.")





stock_name = get_stock_name("Enter the name of the file ==> ", "w")



stock_date = datetime.datetime.strptime(get_stock_date("Enter the stock purchase date ==> " , "%m/%d/%Y"))



stock_sold = datetime.datetime.strptime(get_stock_date("Enter the date you sold the stock ==>" , "%m/%d/%Y"))



stock_purchased = get_stock_purchased("How many stocks were purchased on start date ==>")

edited Apr 11 '16 at 4:38

asked Apr 11 '16 at 4:22

tokyolerd

227

How could there be a TypeError or ValueError if all you're doing is input()? And if it succeeds, it stops the function. I think you need to have another look at while, return, and possibly break. Oh, and also at recursion. And saving references.

– TigerhawkT3
Apr 11 '16 at 4:26

The exception is raised in python 2? What do you input?

– tdelaney
Apr 11 '16 at 4:28

@TigerhawkT3 Thanks! And while I was messing around with it, it gave me two different errors (TypeError and ValueError) So that's why I made two exceptions.

– tokyolerd
Apr 11 '16 at 4:30

@tdelaney Python 3. If I input 5/10/2004 it will move on, but if I input anything else, It will give me a ValueError.

– tokyolerd
Apr 11 '16 at 4:31

Also, your parens are messed up - you're sending two arguments to the recursive call of get_stock_date and only one to strptime.

– TigerhawkT3
Apr 11 '16 at 4:32

|
show 4 more comments

-2

Here is my code:

 import datetime

import csv





def get_stock_name(prompt,mode):

    while True:

        try:

            return open(input(prompt) + ".csv")

        except FileNotFoundError:

            print("File not found. Please try again.")

        except IOError:

            print("There was an IOError opening the file. Please try again.")





def get_stock_date(prompt):

    while True:

        try:

            return (input(prompt))

        except TypeError:

            print("Try again.")

        except ValueError:

            print("Try again.")





def get_stock_purchased(prompt):

    while True:

        try:

            return (input(prompt))

        except ValueError:

            print("Try again.")

        except TypeError:

            print("try again.")





stock_name = get_stock_name("Enter the name of the file ==> ", "w")



stock_date = datetime.datetime.strptime(get_stock_date("Enter the stock purchase date ==> " , "%m/%d/%Y"))



stock_sold = datetime.datetime.strptime(get_stock_date("Enter the date you sold the stock ==>" , "%m/%d/%Y"))



stock_purchased = get_stock_purchased("How many stocks were purchased on start date ==>")

edited Apr 11 '16 at 4:38

asked Apr 11 '16 at 4:22

tokyolerd

227

Here is my code:

 import datetime

import csv





def get_stock_name(prompt,mode):

    while True:

        try:

            return open(input(prompt) + ".csv")

        except FileNotFoundError:

            print("File not found. Please try again.")

        except IOError:

            print("There was an IOError opening the file. Please try again.")





def get_stock_date(prompt):

    while True:

        try:

            return (input(prompt))

        except TypeError:

            print("Try again.")

        except ValueError:

            print("Try again.")





def get_stock_purchased(prompt):

    while True:

        try:

            return (input(prompt))

        except ValueError:

            print("Try again.")

        except TypeError:

            print("try again.")





stock_name = get_stock_name("Enter the name of the file ==> ", "w")



stock_date = datetime.datetime.strptime(get_stock_date("Enter the stock purchase date ==> " , "%m/%d/%Y"))



stock_sold = datetime.datetime.strptime(get_stock_date("Enter the date you sold the stock ==>" , "%m/%d/%Y"))



stock_purchased = get_stock_purchased("How many stocks were purchased on start date ==>")

python function datetime try-except

edited Apr 11 '16 at 4:38

asked Apr 11 '16 at 4:22

tokyolerd

227

edited Apr 11 '16 at 4:38

asked Apr 11 '16 at 4:22

tokyolerd

227

edited Apr 11 '16 at 4:38

asked Apr 11 '16 at 4:22

tokyolerd

227

asked Apr 11 '16 at 4:22

tokyolerd

227

asked Apr 11 '16 at 4:22

tokyolerd

227

How could there be a TypeError or ValueError if all you're doing is input()? And if it succeeds, it stops the function. I think you need to have another look at while, return, and possibly break. Oh, and also at recursion. And saving references.

– TigerhawkT3
Apr 11 '16 at 4:26

The exception is raised in python 2? What do you input?

– tdelaney
Apr 11 '16 at 4:28

@TigerhawkT3 Thanks! And while I was messing around with it, it gave me two different errors (TypeError and ValueError) So that's why I made two exceptions.

– tokyolerd
Apr 11 '16 at 4:30

@tdelaney Python 3. If I input 5/10/2004 it will move on, but if I input anything else, It will give me a ValueError.

– tokyolerd
Apr 11 '16 at 4:31

Also, your parens are messed up - you're sending two arguments to the recursive call of get_stock_date and only one to strptime.

– TigerhawkT3
Apr 11 '16 at 4:32

|
show 4 more comments

How could there be a TypeError or ValueError if all you're doing is input()? And if it succeeds, it stops the function. I think you need to have another look at while, return, and possibly break. Oh, and also at recursion. And saving references.

– TigerhawkT3
Apr 11 '16 at 4:26

The exception is raised in python 2? What do you input?

– tdelaney
Apr 11 '16 at 4:28

@TigerhawkT3 Thanks! And while I was messing around with it, it gave me two different errors (TypeError and ValueError) So that's why I made two exceptions.

– tokyolerd
Apr 11 '16 at 4:30

@tdelaney Python 3. If I input 5/10/2004 it will move on, but if I input anything else, It will give me a ValueError.

– tokyolerd
Apr 11 '16 at 4:31

Also, your parens are messed up - you're sending two arguments to the recursive call of get_stock_date and only one to strptime.

– TigerhawkT3
Apr 11 '16 at 4:32

How could there be a TypeError or ValueError if all you're doing is input()? And if it succeeds, it stops the function. I think you need to have another look at while, return, and possibly break. Oh, and also at recursion. And saving references.

– TigerhawkT3
Apr 11 '16 at 4:26

The exception is raised in python 2? What do you input?

– tdelaney
Apr 11 '16 at 4:28

@TigerhawkT3 Thanks! And while I was messing around with it, it gave me two different errors (TypeError and ValueError) So that's why I made two exceptions.

– tokyolerd
Apr 11 '16 at 4:30

@tdelaney Python 3. If I input 5/10/2004 it will move on, but if I input anything else, It will give me a ValueError.

– tokyolerd
Apr 11 '16 at 4:31

Also, your parens are messed up - you're sending two arguments to the recursive call of get_stock_date and only one to strptime.

– TigerhawkT3
Apr 11 '16 at 4:32

|
show 4 more comments

3 Answers
3

active

oldest

votes

To clarify Tigerhawk's initial comment: in order for the try-catch to handle TypeError or ValueError, you need to cast the input to datetime in the try statement.

import datetime



def get_stock_date(prompt):

  while True:

    try:

      return datetime.datetime.strptime(input(prompt), "%m/%d/%Y")

    except (ValueError, TypeError):

      print("Try again.")



stock_date = get_stock_date("Enter the stock purchase date ==> ")

Additionally, your initial post had strange indentation that made it look like you were making a recursive call to get_stock_date, which caused confusion.

Lastly, you will need to use raw_input if you're using Python 2.

answered Apr 11 '16 at 4:46

James Buerger

1946

add a comment |

You currently have a loop that will immediately end the function and return a string in any situation I can think of off the top of my head, exceptions that (as just mentioned) I don't think will happen, a call to strptime with the wrong number of arguments, and a recursive call to your function with the wrong number of arguments. And you never save or return a meaningful value. Maybe the recursive call just has wrong indentation? Anyway, you'll have to completely restructure your code, as most of it makes little sense:

import datetime

def get_stock_date(prompt):

    while True:

        d = input(prompt)

        try:

            d = datetime.datetime.strptime(d, "%m/%d/%Y")

        except (ValueError, TypeError):

            print("Try again.")

        else:

            return d



stock_date = get_stock_date("Enter the stock purchase date ==> ")

answered Apr 11 '16 at 4:38

TigerhawkT3

39.7k53566

Thank you! I got a little confused with your explanation, but James kind of made it clearer.

– tokyolerd
Apr 11 '16 at 4:49

add a comment |

-1

I think this is what you are looking for:

def get_stock_date(prompt):

    try:

        stock_date = datetime.datetime.strptime(prompt, "%m/%d/%Y")

        return(stock_date)

    except:

        print("Try Again.")

        prompt = input("Enter the stock purchase date ==> ")

        get_stock_date(prompt)



get_stock_date(input("Enter the stock purchase date ==> " ))

edited Apr 11 '16 at 5:15

answered Apr 11 '16 at 4:45

Shobeir

977

You are converting the passed prompt, which will fail, and then getting a new value with a bare input() call (without the "Enter the stock purchase..." prompt).

– TigerhawkT3
Apr 11 '16 at 4:56

Thanks. Yes, that was the idea. I wanted it to ask the user to enter a valid value.

– Shobeir
Apr 11 '16 at 5:18

add a comment |

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3 Answers
3

active

oldest

votes

3 Answers
3

active

oldest

votes

To clarify Tigerhawk's initial comment: in order for the try-catch to handle TypeError or ValueError, you need to cast the input to datetime in the try statement.

import datetime



def get_stock_date(prompt):

  while True:

    try:

      return datetime.datetime.strptime(input(prompt), "%m/%d/%Y")

    except (ValueError, TypeError):

      print("Try again.")



stock_date = get_stock_date("Enter the stock purchase date ==> ")

Additionally, your initial post had strange indentation that made it look like you were making a recursive call to get_stock_date, which caused confusion.

Lastly, you will need to use raw_input if you're using Python 2.

answered Apr 11 '16 at 4:46

James Buerger

1946

add a comment |

To clarify Tigerhawk's initial comment: in order for the try-catch to handle TypeError or ValueError, you need to cast the input to datetime in the try statement.

import datetime



def get_stock_date(prompt):

  while True:

    try:

      return datetime.datetime.strptime(input(prompt), "%m/%d/%Y")

    except (ValueError, TypeError):

      print("Try again.")



stock_date = get_stock_date("Enter the stock purchase date ==> ")

Additionally, your initial post had strange indentation that made it look like you were making a recursive call to get_stock_date, which caused confusion.

Lastly, you will need to use raw_input if you're using Python 2.

answered Apr 11 '16 at 4:46

James Buerger

1946

add a comment |

To clarify Tigerhawk's initial comment: in order for the try-catch to handle TypeError or ValueError, you need to cast the input to datetime in the try statement.

import datetime



def get_stock_date(prompt):

  while True:

    try:

      return datetime.datetime.strptime(input(prompt), "%m/%d/%Y")

    except (ValueError, TypeError):

      print("Try again.")



stock_date = get_stock_date("Enter the stock purchase date ==> ")

Additionally, your initial post had strange indentation that made it look like you were making a recursive call to get_stock_date, which caused confusion.

Lastly, you will need to use raw_input if you're using Python 2.

answered Apr 11 '16 at 4:46

James Buerger

1946

To clarify Tigerhawk's initial comment: in order for the try-catch to handle TypeError or ValueError, you need to cast the input to datetime in the try statement.

import datetime



def get_stock_date(prompt):

  while True:

    try:

      return datetime.datetime.strptime(input(prompt), "%m/%d/%Y")

    except (ValueError, TypeError):

      print("Try again.")



stock_date = get_stock_date("Enter the stock purchase date ==> ")

Additionally, your initial post had strange indentation that made it look like you were making a recursive call to get_stock_date, which caused confusion.

Lastly, you will need to use raw_input if you're using Python 2.

answered Apr 11 '16 at 4:46

James Buerger

1946

answered Apr 11 '16 at 4:46

James Buerger

1946

answered Apr 11 '16 at 4:46

James Buerger

1946

answered Apr 11 '16 at 4:46

James Buerger

1946

add a comment |

import datetime

def get_stock_date(prompt):

    while True:

        d = input(prompt)

        try:

            d = datetime.datetime.strptime(d, "%m/%d/%Y")

        except (ValueError, TypeError):

            print("Try again.")

        else:

            return d



stock_date = get_stock_date("Enter the stock purchase date ==> ")

answered Apr 11 '16 at 4:38

TigerhawkT3

39.7k53566

Thank you! I got a little confused with your explanation, but James kind of made it clearer.

– tokyolerd
Apr 11 '16 at 4:49

add a comment |

import datetime

def get_stock_date(prompt):

    while True:

        d = input(prompt)

        try:

            d = datetime.datetime.strptime(d, "%m/%d/%Y")

        except (ValueError, TypeError):

            print("Try again.")

        else:

            return d



stock_date = get_stock_date("Enter the stock purchase date ==> ")

answered Apr 11 '16 at 4:38

TigerhawkT3

39.7k53566

Thank you! I got a little confused with your explanation, but James kind of made it clearer.

– tokyolerd
Apr 11 '16 at 4:49

add a comment |

import datetime

def get_stock_date(prompt):

    while True:

        d = input(prompt)

        try:

            d = datetime.datetime.strptime(d, "%m/%d/%Y")

        except (ValueError, TypeError):

            print("Try again.")

        else:

            return d



stock_date = get_stock_date("Enter the stock purchase date ==> ")

answered Apr 11 '16 at 4:38

TigerhawkT3

39.7k53566

import datetime

def get_stock_date(prompt):

    while True:

        d = input(prompt)

        try:

            d = datetime.datetime.strptime(d, "%m/%d/%Y")

        except (ValueError, TypeError):

            print("Try again.")

        else:

            return d



stock_date = get_stock_date("Enter the stock purchase date ==> ")

answered Apr 11 '16 at 4:38

TigerhawkT3

39.7k53566

answered Apr 11 '16 at 4:38

TigerhawkT3

39.7k53566

answered Apr 11 '16 at 4:38

TigerhawkT3

39.7k53566

answered Apr 11 '16 at 4:38

TigerhawkT3

39.7k53566

Thank you! I got a little confused with your explanation, but James kind of made it clearer.

– tokyolerd
Apr 11 '16 at 4:49

add a comment |

Thank you! I got a little confused with your explanation, but James kind of made it clearer.

– tokyolerd
Apr 11 '16 at 4:49

Thank you! I got a little confused with your explanation, but James kind of made it clearer.

– tokyolerd
Apr 11 '16 at 4:49

add a comment |

-1

I think this is what you are looking for:

def get_stock_date(prompt):

    try:

        stock_date = datetime.datetime.strptime(prompt, "%m/%d/%Y")

        return(stock_date)

    except:

        print("Try Again.")

        prompt = input("Enter the stock purchase date ==> ")

        get_stock_date(prompt)



get_stock_date(input("Enter the stock purchase date ==> " ))

edited Apr 11 '16 at 5:15

answered Apr 11 '16 at 4:45

Shobeir

977

You are converting the passed prompt, which will fail, and then getting a new value with a bare input() call (without the "Enter the stock purchase..." prompt).

– TigerhawkT3
Apr 11 '16 at 4:56

Thanks. Yes, that was the idea. I wanted it to ask the user to enter a valid value.

– Shobeir
Apr 11 '16 at 5:18

add a comment |

-1

I think this is what you are looking for:

def get_stock_date(prompt):

    try:

        stock_date = datetime.datetime.strptime(prompt, "%m/%d/%Y")

        return(stock_date)

    except:

        print("Try Again.")

        prompt = input("Enter the stock purchase date ==> ")

        get_stock_date(prompt)



get_stock_date(input("Enter the stock purchase date ==> " ))

edited Apr 11 '16 at 5:15

answered Apr 11 '16 at 4:45

Shobeir

977

You are converting the passed prompt, which will fail, and then getting a new value with a bare input() call (without the "Enter the stock purchase..." prompt).

– TigerhawkT3
Apr 11 '16 at 4:56

Thanks. Yes, that was the idea. I wanted it to ask the user to enter a valid value.

– Shobeir
Apr 11 '16 at 5:18

add a comment |

-1

I think this is what you are looking for:

def get_stock_date(prompt):

    try:

        stock_date = datetime.datetime.strptime(prompt, "%m/%d/%Y")

        return(stock_date)

    except:

        print("Try Again.")

        prompt = input("Enter the stock purchase date ==> ")

        get_stock_date(prompt)



get_stock_date(input("Enter the stock purchase date ==> " ))

edited Apr 11 '16 at 5:15

answered Apr 11 '16 at 4:45

Shobeir

977

I think this is what you are looking for:

def get_stock_date(prompt):

    try:

        stock_date = datetime.datetime.strptime(prompt, "%m/%d/%Y")

        return(stock_date)

    except:

        print("Try Again.")

        prompt = input("Enter the stock purchase date ==> ")

        get_stock_date(prompt)



get_stock_date(input("Enter the stock purchase date ==> " ))

edited Apr 11 '16 at 5:15

answered Apr 11 '16 at 4:45

Shobeir

977

edited Apr 11 '16 at 5:15

answered Apr 11 '16 at 4:45

Shobeir

977

answered Apr 11 '16 at 4:45

Shobeir

977

answered Apr 11 '16 at 4:45

Shobeir

977

You are converting the passed prompt, which will fail, and then getting a new value with a bare input() call (without the "Enter the stock purchase..." prompt).

– TigerhawkT3
Apr 11 '16 at 4:56

Thanks. Yes, that was the idea. I wanted it to ask the user to enter a valid value.

– Shobeir
Apr 11 '16 at 5:18

add a comment |

You are converting the passed prompt, which will fail, and then getting a new value with a bare input() call (without the "Enter the stock purchase..." prompt).

– TigerhawkT3
Apr 11 '16 at 4:56

Thanks. Yes, that was the idea. I wanted it to ask the user to enter a valid value.

– Shobeir
Apr 11 '16 at 5:18

You are converting the passed prompt, which will fail, and then getting a new value with a bare input() call (without the "Enter the stock purchase..." prompt).

– TigerhawkT3
Apr 11 '16 at 4:56

Thanks. Yes, that was the idea. I wanted it to ask the user to enter a valid value.

– Shobeir
Apr 11 '16 at 5:18

add a comment |

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