Python - 遍历用户输入的数字，计算并输出输入的值

Question

I have been learning Python for nearly 6 weeks now and below is my first program.

What I would like to get are user input for patient no, carb, protein and fat requirement.

With the below code, I get the output that I want. However, I feel that it is not DRY at all. I am repeating a lot of things.

I want to modify this code to enable users to enter as many patients as they like. Currently, I specify patient_no1 and patient_no2. I am going to revise for loop and code this problem with for loop. If you could give me a bit guidance on how I could refactor this current code, it would be greatly appreciated. Thank you!

def diet_log():

    ################################ Patient 1 ##########################################
    # Request User input for patient numbers, Handle non-positive integers and other invalid user input error for patient numbers 
    while True:
        try:
            patient_no1 = int(input("Enter a patient number to determine the dietary requirements : "))
            assert(patient_no1 > 0), "The patient number entered must be a positive integer."
            break           
        except:
            print("The patient number you enter must be a positive integer. Please try again.")

    # Request User input for protein, Handle non-positive integers and other invalid user input error 

    while True:
        try:
            diet_protein1 = float(input("Amount of protein required: "))
            assert(diet_protein1 > 0)
            break           
        except:
            print("The protein amount must be a non-negative integer.")

    # Request User input for carbohydrates, Handle non-positive integers and other invalid user input error 

    while True:
        try:
            diet_carb1 = float(input("Amount of carbohydrates required: "))
            assert(diet_carb1 > 0)
            break           
        except:
            print("The amount of carbohydrates required must be a non-negative integer.")

    # Request User input for fat, Handle non-positive integers and other invalid user input error 

    while True:
        try:
            diet_fat1 = float(input("Amount of fat required:  "))
            assert(diet_fat1 > 0)
            break           
        except:
            print("The fat amount must be a non-negative integer.")

    print("-----------------------------------------------------")

    ########################## end of Patient 1 ##############################################################


    ################################ Patient 2 ##########################################
    # Request User input for patient numbers, Handle non-positive integers and other invalid user input error for patient numbers 
    while True:
        try:
            patient_no2 = int(input("Enter a patient number to determine the dietary requirements : "))
            assert(patient_no2 > 0), "The patient number entered must be a positive integer."
            break           
        except:
            print("The patient number you enter must be a positive integer. Please try again.")

    # Request User input for protein, Handle non-positive integers and other invalid user input error 

    while True:
        try:
            diet_protein2 = float(input("Amount of protein required: "))
            assert(diet_protein2 > 0)
            break           
        except:
            print("The protein amount must be a non-negative integer.")

    # Request User input for carbohydrates, Handle non-positive integers and other invalid user input error 

    while True:
        try:
            diet_carb2 = float(input("Amount of carbohydrates required: "))
            assert(diet_carb2 > 0)
            break           
        except:
            print("The amount of carbohydrates required must be a non-negative integer.")

    # Request User input for fat, Handle non-positive integers and other invalid user input error 

    while True:
        try:
            diet_fat2 = float(input("Amount of fat required:  "))
            assert(diet_fat2 > 0)
            break           
        except:
            print("The fat amount must be a non-negative integer.")

    ########################## end of Patient 2 ##############################################################

    # Create list of protein, carb and fat for patients 

    total_patient_num = [patient_no1, patient_no2]
    diet_protein = [diet_protein1, diet_protein2]
    diet_carb = [diet_carb1, diet_carb2]
    diet_fat = [diet_fat1, diet_fat2]

    # Calculate average for the lists created above by using statistics 
    import statistics

    average_protein = statistics.mean(diet_protein)
    average_carb = statistics.mean(diet_carb)
    average_fat = statistics.mean(diet_fat)

    # Calculate average kilojoules 

    kilojoules = 4.18 * ( (4 * average_protein) + (4* average_carb) + (9.30 * average_fat)) 

    # Display the output to the users 
    print("===================================================")
    print("Total number of patients entered: ", len(total_patient_num))

    print("Patient %d" % patient_no1)
    print("\n","   Amount of protein (g) required: ", diet_protein1, "\n","   Amount of carbohydrates (g) required: ",diet_carb1 ,"\n","   Amount of fat required: ", diet_fat1) 


    print("Patient %d" % patient_no2)
    print("\n","   Amount of protein (g) required: ", diet_protein2, "\n","   Amount of carbohydrates (g) required: ",diet_carb2 ,"\n","   Amount of fat required: ", diet_fat2) 

    print("-----------------------------------------------------")
    print("Averages: ", "\n", 
        "Protein (g): ", format(average_protein, ",.2f"), "\n", 
        "Carbohydrates (g): ", format(average_carb, ",.2f"), "\n",
        "Fat (g): ", format(average_fat, ".2f"), "\n", 
        "Kilojoules (kJ): ", format(kilojoules, ",.2f"), "\n")

if __name__ == "__main__": diet_log()
    # print(diet_log("patient no"))

Answer 1

Start by looking for code that looks really similar. For instance the while loops that you are performing around input statements look a lot alike. Try turning these into functions with parameters for the parts that make them different.

Answer 2

You could start by defining your lists in a generic way:

total_patient_num = []
diet_protein = []
diet_carb = []
diet_fat = []

Currently, you would have to repeat the same code n times if you were to add n users. When you see patterns like this, it hints you towards the fact that you should be abstracting your code. To fix this you could simply get the code into a function as such:

def get_user_input():
    while True:
        try:
            patient_no_value = int(input("Enter a patient number to determine the dietary requirements : "))
            assert(patient_no_value > 0), "The patient number entered must be a positive integer."
            total_patient_num.append(patient_no_value)
            break           
        except:
            print("The patient number you enter must be a positive integer. Please try again.")

    # Request User input for protein, Handle non-positive integers and other invalid user input error 

    while True:
        try:
            diet_protein_value = float(input("Amount of protein required: "))
            assert(diet_protein_value > 0)
            diet_protein.append(diet_protein_value)
            break           
        except:
            print("The protein amount must be a non-negative integer.")

    # Request User input for carbohydrates, Handle non-positive integers and other invalid user input error 

    while True:
        try:
            diet_carb_value = float(input("Amount of carbohydrates required: "))
            assert(diet_carb_value > 0)
            diet_carb.apend(diet_carb_value )
            break           
        except:
            print("The amount of carbohydrates required must be a non-negative integer.")

    # Request User input for fat, Handle non-positive integers and other invalid user input error 

    while True:
        try:
            diet_fat_value = float(input("Amount of fat required:  "))
            assert(diet_fat_value > 0)
            diet_fat.append(diet_fat_value)
            break           
        except:
            print("The fat amount must be a non-negative integer.")

    print("-----------------------------------------------------")

Each time you call that method, it'll create a new entry on each of those lists.

You could also think about using a class to represent your user.