How to validate array for negative # and alpha input in Python

I'm trying to validate an array of user inputs (pints of blood collected per hour over 7 hours) for negative numbers, spaces, and/or letters. Currently, with an if statement checking user input is below 0, the program receives type error: "'<' not supported between instances of 'list' and 'int'."

inputPints = 

totalPints = 0

hours = ["#1", "#2", "#3", "#4", "#5", "#6", "#7"]



def userInput():

    for hour in hours:

        inputPints.append(int(input("Enter pints collected for hour {}: ".format(hour))))

        if inputPints<0:

            inputPints.append(int(input("Please enter a whole number {}: ".format(hour))))

userInput()



def userOutput():

    print("")

    print("Average number of pints donated is: ", "{:.2f}".format(import_functions.averagePints(totalPints, 7)))

    print("Most pints donated is: ", import_functions.maxPints())

    print("Least pints donated is: ", import_functions.minPints())

    print("")

userOutput()

asked Nov 22 '18 at 21:57

Kyle Barnes

Are you looking for if len(inputPints) < 0? Because you're comparing a list with the integer 0.. Just as the error says. Or are you looking for if len(inputPints[-1]) < 0 if the last input is length below zero?

– Torxed
Nov 22 '18 at 21:58

Why do you perform the check after having appended the input already? How do you want to recover from the erroneous value? How do you want to deal with repeated incorrect input?

– MisterMiyagi
Nov 22 '18 at 22:03

Great questions. I honestly couldn't tell you as I'm new to Python as of about 6 weeks ago. I've tried the length function and it returns no errors, but it doesn't show the user they are inputting an invalid integer.

– Kyle Barnes
Nov 22 '18 at 22:16

add a comment |

inputPints = 

totalPints = 0

hours = ["#1", "#2", "#3", "#4", "#5", "#6", "#7"]



def userInput():

    for hour in hours:

        inputPints.append(int(input("Enter pints collected for hour {}: ".format(hour))))

        if inputPints<0:

            inputPints.append(int(input("Please enter a whole number {}: ".format(hour))))

userInput()



def userOutput():

    print("")

    print("Average number of pints donated is: ", "{:.2f}".format(import_functions.averagePints(totalPints, 7)))

    print("Most pints donated is: ", import_functions.maxPints())

    print("Least pints donated is: ", import_functions.minPints())

    print("")

userOutput()

asked Nov 22 '18 at 21:57

Kyle Barnes

Are you looking for if len(inputPints) < 0? Because you're comparing a list with the integer 0.. Just as the error says. Or are you looking for if len(inputPints[-1]) < 0 if the last input is length below zero?

– Torxed
Nov 22 '18 at 21:58

Why do you perform the check after having appended the input already? How do you want to recover from the erroneous value? How do you want to deal with repeated incorrect input?

– MisterMiyagi
Nov 22 '18 at 22:03

Great questions. I honestly couldn't tell you as I'm new to Python as of about 6 weeks ago. I've tried the length function and it returns no errors, but it doesn't show the user they are inputting an invalid integer.

– Kyle Barnes
Nov 22 '18 at 22:16

add a comment |

inputPints = 

totalPints = 0

hours = ["#1", "#2", "#3", "#4", "#5", "#6", "#7"]



def userInput():

    for hour in hours:

        inputPints.append(int(input("Enter pints collected for hour {}: ".format(hour))))

        if inputPints<0:

            inputPints.append(int(input("Please enter a whole number {}: ".format(hour))))

userInput()



def userOutput():

    print("")

    print("Average number of pints donated is: ", "{:.2f}".format(import_functions.averagePints(totalPints, 7)))

    print("Most pints donated is: ", import_functions.maxPints())

    print("Least pints donated is: ", import_functions.minPints())

    print("")

userOutput()

asked Nov 22 '18 at 21:57

Kyle Barnes

inputPints = 

totalPints = 0

hours = ["#1", "#2", "#3", "#4", "#5", "#6", "#7"]



def userInput():

    for hour in hours:

        inputPints.append(int(input("Enter pints collected for hour {}: ".format(hour))))

        if inputPints<0:

            inputPints.append(int(input("Please enter a whole number {}: ".format(hour))))

userInput()



def userOutput():

    print("")

    print("Average number of pints donated is: ", "{:.2f}".format(import_functions.averagePints(totalPints, 7)))

    print("Most pints donated is: ", import_functions.maxPints())

    print("Least pints donated is: ", import_functions.minPints())

    print("")

userOutput()

python validation

asked Nov 22 '18 at 21:57

Kyle Barnes

asked Nov 22 '18 at 21:57

Kyle Barnes

asked Nov 22 '18 at 21:57

Kyle Barnes

asked Nov 22 '18 at 21:57

Kyle Barnes

asked Nov 22 '18 at 21:57

Kyle Barnes

Are you looking for if len(inputPints) < 0? Because you're comparing a list with the integer 0.. Just as the error says. Or are you looking for if len(inputPints[-1]) < 0 if the last input is length below zero?

– Torxed
Nov 22 '18 at 21:58

Why do you perform the check after having appended the input already? How do you want to recover from the erroneous value? How do you want to deal with repeated incorrect input?

– MisterMiyagi
Nov 22 '18 at 22:03

Great questions. I honestly couldn't tell you as I'm new to Python as of about 6 weeks ago. I've tried the length function and it returns no errors, but it doesn't show the user they are inputting an invalid integer.

– Kyle Barnes
Nov 22 '18 at 22:16

add a comment |

Are you looking for if len(inputPints) < 0? Because you're comparing a list with the integer 0.. Just as the error says. Or are you looking for if len(inputPints[-1]) < 0 if the last input is length below zero?

– Torxed
Nov 22 '18 at 21:58

Why do you perform the check after having appended the input already? How do you want to recover from the erroneous value? How do you want to deal with repeated incorrect input?

– MisterMiyagi
Nov 22 '18 at 22:03

Great questions. I honestly couldn't tell you as I'm new to Python as of about 6 weeks ago. I've tried the length function and it returns no errors, but it doesn't show the user they are inputting an invalid integer.

– Kyle Barnes
Nov 22 '18 at 22:16

Are you looking for if len(inputPints) < 0? Because you're comparing a list with the integer 0.. Just as the error says. Or are you looking for if len(inputPints[-1]) < 0 if the last input is length below zero?

– Torxed
Nov 22 '18 at 21:58

Why do you perform the check after having appended the input already? How do you want to recover from the erroneous value? How do you want to deal with repeated incorrect input?

– MisterMiyagi
Nov 22 '18 at 22:03

Great questions. I honestly couldn't tell you as I'm new to Python as of about 6 weeks ago. I've tried the length function and it returns no errors, but it doesn't show the user they are inputting an invalid integer.

– Kyle Barnes
Nov 22 '18 at 22:16

add a comment |

3 Answers
3

active

oldest

votes

I think you should define your userInput() method like this …

def userInput():

    for hour in hours:

        user_input = -1

        while user_input < 0:

            try:

                user_input = int(input("Enter pints collected for hour {}: ".format(hour)))

            except:

                user_input = -1

            if user_input > -1:

                inputPints.append(user_input)

answered Nov 22 '18 at 22:17

Red Cricket

4,389103384

add a comment |

You can use regex to validade your input.
To allow only the form #number.numbers, you can use the following for instance:

# test for matches on the regex expression. 

if len(re.findall('^#d+.d+$', "#-1.30")) > 0:

    # It is valid

    return true

answered Nov 22 '18 at 22:08

Pedro Torres

683413

add a comment |

Just as Torxed commented, you are comparing an object of the "list" type vs an object of the "int" type. This rises the error:
"'<' not supported between instances of 'list' and 'int'."

Yo should either validate user input before appending it to the list, or you could loop over the complete list to find wrong/right inputs.

-Checking input before appending:

if int(input("Enter pints collected for hour {}: ".format(hours))) > 1:

    #This is ok

-Checking input with complete list

for a in inputPints:

    if int(a) > 1:

        #a is OK.

I reccomend you put those validations inside a try catch block, since the int() casting may break your code if it detects a non-castable character.

Hope this helps!

Regards

answered Nov 22 '18 at 22:29

Santiago Peron

add a comment |

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3 Answers
3

active

oldest

votes

3 Answers
3

active

oldest

votes

I think you should define your userInput() method like this …

def userInput():

    for hour in hours:

        user_input = -1

        while user_input < 0:

            try:

                user_input = int(input("Enter pints collected for hour {}: ".format(hour)))

            except:

                user_input = -1

            if user_input > -1:

                inputPints.append(user_input)

answered Nov 22 '18 at 22:17

Red Cricket

4,389103384

add a comment |

I think you should define your userInput() method like this …

def userInput():

    for hour in hours:

        user_input = -1

        while user_input < 0:

            try:

                user_input = int(input("Enter pints collected for hour {}: ".format(hour)))

            except:

                user_input = -1

            if user_input > -1:

                inputPints.append(user_input)

answered Nov 22 '18 at 22:17

Red Cricket

4,389103384

add a comment |

I think you should define your userInput() method like this …

def userInput():

    for hour in hours:

        user_input = -1

        while user_input < 0:

            try:

                user_input = int(input("Enter pints collected for hour {}: ".format(hour)))

            except:

                user_input = -1

            if user_input > -1:

                inputPints.append(user_input)

answered Nov 22 '18 at 22:17

Red Cricket

4,389103384

I think you should define your userInput() method like this …

def userInput():

    for hour in hours:

        user_input = -1

        while user_input < 0:

            try:

                user_input = int(input("Enter pints collected for hour {}: ".format(hour)))

            except:

                user_input = -1

            if user_input > -1:

                inputPints.append(user_input)

answered Nov 22 '18 at 22:17

Red Cricket

4,389103384

answered Nov 22 '18 at 22:17

Red Cricket

4,389103384

answered Nov 22 '18 at 22:17

Red Cricket

4,389103384

answered Nov 22 '18 at 22:17

Red Cricket

4,389103384

add a comment |

You can use regex to validade your input.
To allow only the form #number.numbers, you can use the following for instance:

# test for matches on the regex expression. 

if len(re.findall('^#d+.d+$', "#-1.30")) > 0:

    # It is valid

    return true

answered Nov 22 '18 at 22:08

Pedro Torres

683413

add a comment |

You can use regex to validade your input.
To allow only the form #number.numbers, you can use the following for instance:

# test for matches on the regex expression. 

if len(re.findall('^#d+.d+$', "#-1.30")) > 0:

    # It is valid

    return true

answered Nov 22 '18 at 22:08

Pedro Torres

683413

add a comment |

You can use regex to validade your input.
To allow only the form #number.numbers, you can use the following for instance:

# test for matches on the regex expression. 

if len(re.findall('^#d+.d+$', "#-1.30")) > 0:

    # It is valid

    return true

answered Nov 22 '18 at 22:08

Pedro Torres

683413

You can use regex to validade your input.
To allow only the form #number.numbers, you can use the following for instance:

# test for matches on the regex expression. 

if len(re.findall('^#d+.d+$', "#-1.30")) > 0:

    # It is valid

    return true

answered Nov 22 '18 at 22:08

Pedro Torres

683413

answered Nov 22 '18 at 22:08

Pedro Torres

683413

answered Nov 22 '18 at 22:08

Pedro Torres

683413

answered Nov 22 '18 at 22:08

Pedro Torres

683413

add a comment |

Just as Torxed commented, you are comparing an object of the "list" type vs an object of the "int" type. This rises the error:
"'<' not supported between instances of 'list' and 'int'."

Yo should either validate user input before appending it to the list, or you could loop over the complete list to find wrong/right inputs.

-Checking input before appending:

if int(input("Enter pints collected for hour {}: ".format(hours))) > 1:

    #This is ok

-Checking input with complete list

for a in inputPints:

    if int(a) > 1:

        #a is OK.

I reccomend you put those validations inside a try catch block, since the int() casting may break your code if it detects a non-castable character.

Hope this helps!

Regards

answered Nov 22 '18 at 22:29

Santiago Peron

add a comment |

Just as Torxed commented, you are comparing an object of the "list" type vs an object of the "int" type. This rises the error:
"'<' not supported between instances of 'list' and 'int'."

Yo should either validate user input before appending it to the list, or you could loop over the complete list to find wrong/right inputs.

-Checking input before appending:

if int(input("Enter pints collected for hour {}: ".format(hours))) > 1:

    #This is ok

-Checking input with complete list

for a in inputPints:

    if int(a) > 1:

        #a is OK.

I reccomend you put those validations inside a try catch block, since the int() casting may break your code if it detects a non-castable character.

Hope this helps!

Regards

answered Nov 22 '18 at 22:29

Santiago Peron

add a comment |

Just as Torxed commented, you are comparing an object of the "list" type vs an object of the "int" type. This rises the error:
"'<' not supported between instances of 'list' and 'int'."

Yo should either validate user input before appending it to the list, or you could loop over the complete list to find wrong/right inputs.

-Checking input before appending:

if int(input("Enter pints collected for hour {}: ".format(hours))) > 1:

    #This is ok

-Checking input with complete list

for a in inputPints:

    if int(a) > 1:

        #a is OK.

I reccomend you put those validations inside a try catch block, since the int() casting may break your code if it detects a non-castable character.

Hope this helps!

Regards

answered Nov 22 '18 at 22:29

Santiago Peron

Just as Torxed commented, you are comparing an object of the "list" type vs an object of the "int" type. This rises the error:
"'<' not supported between instances of 'list' and 'int'."

Yo should either validate user input before appending it to the list, or you could loop over the complete list to find wrong/right inputs.

-Checking input before appending:

if int(input("Enter pints collected for hour {}: ".format(hours))) > 1:

    #This is ok

-Checking input with complete list

for a in inputPints:

    if int(a) > 1:

        #a is OK.

I reccomend you put those validations inside a try catch block, since the int() casting may break your code if it detects a non-castable character.

Hope this helps!

Regards

answered Nov 22 '18 at 22:29

Santiago Peron

answered Nov 22 '18 at 22:29

Santiago Peron

answered Nov 22 '18 at 22:29

Santiago Peron

answered Nov 22 '18 at 22:29

Santiago Peron

add a comment |

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