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Data validation for multiple user inputs with Python

I am creating a function for my python course that receives a list and returns the same list without the smallest number. However, I wanted to extend the function to ask the user for inputs to create the list after performing some data validations on the inputs.
I was able to validate the first input. However, I got stuck at the second data validation as I need to guarantee that the program should accept only integers in the list and throw and prompt the user again for every wrong input something like while not (type(number) == int) which breaks as soon as the user input matches an int.
How should I do this?
def smallest():
# This function asks the user for a list
# and returns the same list without the smallest number or numbers
list_range = 'Not a number'
list_created = []
while not (type(list_range) == int):
try:
list_range = int(input('Please enter the total number of elements for your list: '))
except:
print('Please provide a number!')
for number in range(1,list_range + 1):
try:
list_element = int(input('Please enter the value of the %d element: ' %number))
list_created.append(list_element)
except:
print('Please provide a number!')
smallest = min(list_created)
result = []
for num in list_created:
if num != smallest:
result.append(num)
return result
Thanks for the help in advance!

You could use a while loop until an int value is entered:
for number in range(1, list_range + 1):
while True:
list_element = input('Please enter the value of the %d element: ' % number)
try:
list_element = int(list_element)
list_created.append(list_element)
break
except ValueError:
print('Please provide a number!')

Using Try and Except to allow bad input still stores the bad input

I am trying to get user input to store some numbers and print out the largest and smallest number. I need to have an except in my code that will print an error message then continue to print my numbers. The problem I am having is if I type a word like cat to get the error message, it also makes the word my largest number. I just want my error message followed by my 2 numbers
l = None
s = None
while True:
num = input('Enter your number')
if num == 'done':
break
try:
num=float(num)
except:
print('Invalid input')
if l is None:
l = num
elif num > l:
l = num
if s is None:
s = num
if num < s:
s = num
print('Maximum is ',l)
print('Minimum is ',s)
any help will be great thanks alot

I would add a continue right after your print('invalid input'). That will make it start the loop again and ask for another number from the user.

How to pop an item of a list as a float

I hope this is more clear:
numbers = [2, 3, 2]
total = 0
while numbers:
total += numbers.pop()
this will return the total valeu of numbers.
Now I must the total valeu of purchase__amount (first code) in this way (second code):
purchase_amount=[]
item=[]
while item != 'done':
item=input("Enter the price, or type 'done' to finnesh ", )
if item != 'done':
if item.isdigit():
purchase_amount.append(item)
else:
print('please type only numbers')
print(purchase_amount)
numbers = [purchase_amount]
total = 0
while numbers:
total += numbers.pop()
print(numbers)
With each atempt though I cant get the numbers from the input in the first code to become a float here and be addet in one number.

There are a few things wrong with your code. One of the main issues being that input returns a string, not a float.
You need to cast the input value from the user. The standard way to do is like so.
item = input("Enter the price, or type 'done'")
if item == 'done':
... # Likely break from your loop
try:
item = float(item)
except ValueError:
print('Invalid input')
The second critical issue is that numbers is a list of list, you should use purchase_amount instead.
Although, poping from the list is unnecessary here as you can simply loop over it or, even better, use sum.
Here is a fixed version of your code.
Fixed code
purchase_amount = []
while True:
item = input("Enter the price, or type 'done'")
if item == 'done':
break
try:
purchase_amount.append(float(item))
except ValueError:
print('Invalid input')
print(purchase_amount)
total = sum(purchase_amount)
print(total)

Python user must only enter float numbers

I am trying to find out how to make it so the user [only enters numbers <0] and [no letters] allowed. Can someone show me how I would set this up. I have tried to set up try/catch blocks but I keep getting errors.
edgeone = input("Enter the first edge of the triangle: ")

I think you want numbers only > 0, or do you want less than zero? Anyway to do this you can using try/except, inside a while loop.
For Python 3, which I think you are using?
goodnumber = False
while not goodnumber:
try:
edgeone = int(input('Enter the first edge of the triangle:'))
if edgeone > 0:
print('thats a good number, thanks')
goodnumber = True
else:
print('thats not a number greater than 0, try again please')
except ValueError:
print('Thats not a number, try again please')
hope this helps.

you must use except handler for this case :
try:
value = int(raw_input("Enter your number:"))
if not ( value < 0 ):
raise ValueError()
except ValueError:
print "you must enter a number <0 "
else:
print value #or something else
Also This question already has an answer here: Accepting only numbers as input in Python

You can do like this.
i = 1
while(type(i)!=float):
i=input("enter no.")
try:
int(i):
except:
try:
i = float(i)
except:
pass
print(i)

Write program that reads numbers while negative number is not entered. Print maximum number among entered values as a result

I've tried to write like:
print "Enter numbers, stops when negative value is entered:"
numbers = [input('value: ') for i in range(10)]
while numbers<0:
but suddenly, I lose my mind, and don't know what to do next
the example is:
Enter numbers, stops when negative value is entered:
value: 5
value: 9
value: 2
value: 4
value: 8
value: -1
Maximum is 9

It sounds like you want something along these lines:
def get_number():
num = 0
while True: # Loop until they enter a number
try:
# Get a string input from the user and try converting to an int
num = int(raw_input('value: '))
break
except ValueError:
# They gave us something that's not an integer - catch it and keep trying
"That's not a number!"
# Done looping, return our number
return num
print "Enter numbers, stops when negative value is entered:"
nums = []
num = get_number() # Initial number - they have to enter at least one (for sanity)
while num >= 0: # While we get positive numbers
# We start with the append so the negative number doesn't end up in the list
nums.append(num)
num = get_number()
print "Max is: {}".format(max(nums))

This is what you're looking for:
print "Enter numbers, stops when negative value is entered:"
nums = []
while True: # infinite loop
try: n = int(raw_input("Enter a number: ")) # raw_input returns a string, so convert to an integer
except ValueError:
n = -1
print "Not a number!"
if n < 0: break # when n is negative, break out of the loop
else: nums.append(n)
print "Maximum number: {}".format(max(nums))

I think you want something like this:
# Show the startup message
print "Enter numbers, stops when negative value is entered:"
# This is the list of numbers
numbers = []
# Loop continuously
while True:
try:
# Get the input and make it an integer
num = int(raw_input("value: "))
# If a ValueError is raised, it means input wasn't a number
except ValueError:
# Jump back to the top of the loop
continue
# Check if the input is positive
if num < 0:
# If we have got here, it means input was bad (negative)
# So, we break the loop
break
# If we have got here, it means input was good
# So, we append it to the list
numbers.append(num)
# Show the maximum number in the list
print "Maximum is", max(numbers)
Demo:
Enter numbers, stops when negative value is entered:
value: 5
value: 9
value: 2
value: 4
value: 8
value: -1
Maximum is 9