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Can anyone solve this problem?

“How Old is Your Dog in Human Years?” Calculator

Write a program that calculates a dog’s age in human years. The program will prompt the user for an age in dog years and calculate that age in human years. Allow for int or float values, but check the user’s input to make sure it's valid -- it should be numeric and positive. Otherwise, let the user know their input is not valid.

You can use the following rules to approximately convert a medium-sized dog’s age to human years:
For the first year, one dog year is equal to 15 human years
For the first 2 years, each dog year is equal to 12 human years
For the first 3 years, each dog year is equal to 9.3 human years
For the first 4 years, each dog year is equal to 8 human years
For the first 5 years, each dog year is equal to 7.2 human years

After that, each dog year is equal to 7 human years. (Note: This means the first 5 dog years are equal to 36 human years (5 * 7.2) and the remaining dog years are equal to 7 human years each.)
Print the result in the following format, substituting for dog_age and human_age: "The given dog age dog_age is human_age in human years." Round the result to 2 decimal places. Note: If there is a 0 in the hundredths place, you can drop it, e.g. 24.00 can be displayed as 24.0.

Considering invalid inputs:
Your program must ask the user for an age in dog years - hint: use the input() function
We are going to test invalid inputs - make sure that your code can handle negative value inputs and non-numerical inputs!

For invalid inputs, make sure that your printed response adheres to the following:
If a text-based input is provided, make sure your response contains the word 'invalid'.
If a negative input is provided, make sure your response contains the word 'negative'.


Use python to code it.





import traceback

def calculator():
 
  # Get dog age
  dog_age = input("Enter your dog's age ")

  try:
  # Cast to float
  dog_age = float(dog_age)

  except:
  print(dog_age, "is an invalid age.")
  print(traceback.format_exc())

calculator()
Yeah, interesting homework...

We are glad to help, but we are not going to do your homework. You need to put some real effort yourself.
(Feb-26-2021, 04:17 PM)buran Wrote: [ -> ]Yeah, interesting homework...

We are glad to help, but we are not going to do your homework. You need to put some real effort yourself.

It is actually not homework but a free course on Coursera. Im 48 years of age and havent done homework for a very long time.

and my effort is below.....


import traceback
def calculator():
    
    # Get dog age
    dog_age = input("Enter the dog's age:")

    try:
        dog_age = float(dog_age)
        dog_age_in_Human_years = 0
        if dog_age < 0 :
            flag = True
        elif 0 < dog_age <= 1 :
            dog_age_in_Human_years += dog_age * 15.0
        elif 1 < dog_age <= 2 :
            dog_age_in_Human_years += dog_age * 12.0
        elif 2 < dog_age <= 3 :
            dog_age_in_Human_years += dog_age * 9.3
        elif 3 < dog_age <= 4 :
            dog_age_in_Human_years += dog_age * 8.0
        elif 4 < dog_age <= 5 :
            dog_age_in_Human_years += dog_age * 7.2
        else:
            dog_age_in_Human_years += 5 * 7.2 + (dog_age - 5) * 7.0 
    except:
        print(dog_age, "is an invalid age.")
        print(traceback.format_exc())
    if flag == False :
        print("The given dog age", dog_age, "is", round(dog_age_in_Human_years, 2), "in human years.")
    else:
        print("Age cannot be a negative number")


calculator()
I'm a lot older than 48 and I am doing homework right now. I figure I'll stop doing homework a few minutes before I stop breathing.

Your "effort" crashes because flag is only defined when the age entered < 0.

I would replace this:
if dog_age < 0 :
    flag = True
with
if dog_age < 0:
    raise ValueError
You already have an exception handler, you may as well use it.

You can also simplify the comparisons and your math:
        if dog_age < 0 :
            raise ValueError
        elif dog_age <= 1 :
            dog_age_in_Human_years = dog_age * 15.0
        elif dog_age <= 2 :
            dog_age_in_Human_years = dog_age * 12.0
(Feb-26-2021, 04:27 PM)Honestworker Wrote: [ -> ]It is actually not homework but a free course on Coursera. Im 48 years of age and havent done homework for a very long time.

homework is not only school "thing". If you prefer let's call it assignment.
If it were me, I'd use a lookup table like this :
human_years_lookup = [0, 15, 24, 27.9, 32, 36]
and then anything over 5 years is 36 + (age_of_dog -5) * 7