My task is to produce a code that greets the user and asks their name storing their name as username. Then generates 2 random numbers and an operation. The question is asked to the user. After that it checks if the users answer is correct or not also adding 1 to questionsAsked. If it is correct, 1 is added to correctAnswers. If it is incorrect, the user is told so with the correct answer. The program should end after 10 questions (hence the while questionAsked > 11). The user should be given their username and how many questions they got correct.
My problem is when I run the code,it comes up with NameError: name 'questionAsked' is not defined. I'm struggling to work out how else I could define questionAsked.
Here is what I've done so far:
import random
import math
def test():
Username=input("What is your name?")
print ("Welcome"+Username+" to the Arithmetic quiz")
num1=random.randint(1, 10)
num2=random.randint(1, 10)
Ops = ['+','-','*']
Operation = random.choice(ops)
num3=int(eval(str(num1) + operation + str(num2)))
print("What is" +" "+str(num1) + operation +str (num2,"?"))
userAnswer= int(input("Your answer:"))
if userAnswer != num3:
print("Incorrect. The right answer is"+" "+(num3))
return False
else:
print("correct")
return True
correctAnswers=0
questionsAsked=0
while questionAsked > 11:
if test () == True:
questionsAnswered +=1
correctAnswers +=1
if test () == False:
questionsAnswered +=1
You have a test while questionAsked > 11 but don't use that name anywhere else in your code. You certainly never defined it. You probably wanted to test questionsAsked (with an s) instead.
There are other problems, however. The loop should continue while you have fewer than 11 questions asked, not more. You also call test() twice, you should only call it once each loop. In your loop you use questionsAnswered but never defined that either and don't increment questionsAsked; you probably meant to increment the latter:
correctAnswers=0
questionsAsked=0
while questionsAsked < 10:
if test():
correctAnswers +=1
questionsAsked +=1
Now test() is only called the once. Both your branches incremented questionsAsked, I moved that out of the tests, and now you no longer need to check if the test failed.
Since you start counting at zero, you want to test for < 10, not 11.
Instead of a while loop, you could use a for loop using the range() function:
for question_number in range(10):
if test():
correctAnswers +=1
Now the for loop takes care of counting the number of questions asked, and you no longer need to increment a variable manually.
Next, you need to move the username handling out of the test() function. You don't need to ask the user for their name each time. Ask for the name once, before the loop, so that you can access the user's name after the 10 questions:
def test():
num1=random.randint(1, 10)
num2=random.randint(1, 10)
# ... etc.
Username = input("What is your name?")
print("Welcome", Username, "to the Arithmetic quiz")
correctAnswers = 0
for question_number in range(10):
if test():
correctAnswers +=1
# print the username and correctAnswers
You need to be careful about your names in the test() function too; you define the names Ops and Operation but try to use them as ops and operation instead. That won't work, you need to use the same case everywhere to refer to those names. The Python style guide recommends you use all lowercase with underscores for local names, to distinguish them from class names (which use CamelCase, initial uppercase letters and no spaces between words).
Next problem: you are using str() with two arguments here:
print("What is" +" "+str(num1) + operation +str (num2,"?"))
That won't work; a two-argument str() call is meant for decoding bytes to a Unicode string.
Rather than use string concatenation, just pass your values to print() as separate arguments. The function will take care of converting things to strings and adds spaces between separate arguments for you:
print("What is", num1, operation, num2, "?")
Now there will be a space between num2 and the "?" but that is not that big a problem. You can use the str.format() method to create a string with placeholders where arguments to the method are filled in for you, again converting to strings automatically. This allows you to control spaces more directly:
print("What is {} {} {}?".format(num1, operation, num2))
The three arguments are placed where each {} appears, in order.
You have many discrepancies in variable names and indentation. Remember Python is case sensitive. And by the way, the condition in your while loop will cause your program not to ask any questions.
So for example, you created a list of operations called Ops and then used the random module to select an operation from ops. Python will inevitably throw an error, as ops is not actually defined. Instead, you should use Ops because that is the variable you actually declared, with a capital letter. Again, Python is case sensitive.
Likewise, Python recognizes a difference between questionAsked and questionsAsked. It's one or the other, so choose a name and be consistent.
Related
I'm "newish" to python programming. I'm trying my best to make my code look nice and function well. I'm using Pycharm as my IDE. I'm doing something for myself. I play tabletop RPG's and I'm attempting to create a character creator for a game I play. I have everything working well, but Pycharm is telling me that "Expression can be simplified" and "PEP 8: E712 comparison to True should be 'if cond is not True:' or 'if not cond:'"
Here is the code in question:
fname = False
while fname != True:
new_character.firstName = input('What would you like your first name to be?\n').capitalize()
if 1 >= len(new_character.firstName) or len(new_character.firstName) > 20:
print('Name does not meet length requirements. Please try again.')
if new_character.firstName.isalpha() != True:
print('Please do not use numbers or special characters in your name. Please try again.')
if (1 < len(new_character.firstName) < 20) and (new_character.firstName.isalpha() == True):
fname = True
Pycharm is telling me that my "while fname != True:" is the part that can be simplified as well as the "if new_character.firstName.isalpha() != True:".
I've tried googling a solution for what I'm doing, but most of them are for something kinda like what I'm asking, but never with the != True portion. I've even reached out to one of my friends that's a python programmer, but I haven't heard back yet.
Again, I want to state that as it is now, the code works correctly the way it is written, I'm just wanting to understand if there is a way to make the code look cleaner/neater or do the same function and be simplified somehow.
Any pointers on how to potentially simplify those lines of code and maintain the functionality would be greatly appreciated.
Here's one way you could rewrite this code to make it easier to read, and more efficient:
# Loop until the user provides a good input
while True:
# Set a temp variable, don't constantly reassign to the new_character.firstName attribute
name = input('What would you like your first name to be?\n').capitalize()
# If the name isn't between 2 and 20 characters, start the loop over at the beginning
if not (1 < len(name) <= 20):
print('Name does not meet length requirements. Please try again.')
continue
# If the name contains anything other than letters, start the loop over at the beginning
if not name.isalpha():
print('Please do not use numbers or special characters in your name. Please try again.')
continue
# You can only reach this break if the name "passed" the two checks above
break
# Finally, assign the character name
new_character.firstName = name
One thing you could do to simplify further is to check both conditions at the same time, and print a more helpful error message that re-states the requirements explicitly:
NAME_ERROR_MESSAGE = """
Invalid name '{name}'. Your character's name
must be between 2 and 20 characters long, and
contain only letters. Please try again.
"""
while True:
name = input('What would you like your first name to be?\n').capitalize()
if (1 < len(name) <= 20) and name.isalpha():
new_character.firstName = name
break
print(NAME_ERROR_MESSAGE.format(name=name)
How to print variable name by input, Example:
a = 1
b = 2
what_variable = input('Which Variable?: ') #User for example introduces 'b'
Console: 2
You can write
print(globals()[what_variable])
but it's not a good approach. Use a dict instead
You can use exec:
var = input('Which Variable?: ')
exec("print(" + var + ")")
Output:
Which Variable?: b
2
>>
Just do the following:
print(eval(input('Which Variable?: ')))
You can also do
print(globals()[input('Which Variable?: ')])
While the other answers seem to address the obvious solution, it's not very 'Pythonic'. The main issues with these is, by far, safety. Let's say that your user inputs apiKey, and you happen to have a variable by that name... let's just say your bank statement is probably looking at a slight increase in magnitude. What most people in these answers don't realise is that using .globals()[input()] is no safer than eval(input()), because, shockingly, people store private info in variables. Alternatively, if it points to a method, e.g
a = print
b = os.system
eval(input())()
I could enter any function name there, and the damage would be done before the second () executes.
Why? Well, let's take a look at how exec and eval work (I won't go into the difference here, see this question for that). All they do is evaluate the string as Python code, and (simplifying here) return the value of the evaluation:
var1 = 3
print(eval("var1"))
# ====is equal to====
var1 = 3
print(var1)
(where var1 as a string obviously comes from the input typed in)
But if someone enters something malicious, this is essentially the basis of an SQL injection:
(where userInput is substituted by a user's input into an input())
userInput = "a + os.system('reboot now')"
print(eval(userInput))
# ====is equal to====
print(a + os.system('shutdown now')
and you suddenly find your computer's off.
Therefore, we'd either use a:
Dictionary (or object): x={a:1, b:2}, then do x[input()]
Array x=[1, 2], then do x[["a", "b"].index(input())]
Simply don't. Find a way to work around it. What's wrong with an if/else set? It's not good practise, because of the safety concerns outlined above. What most people seem to miss about dictionaries (or my array option) is that if you enter a malformed input (i.e not a or b), it would result in either uncaught errors being thrown, or undefineds being thrown around. And if you're going to do input validation, you're using an if statement anyway, so why not do it from the onset?
I made a program in python that is supposed to accept a name as user input. It will then check if the name given is contained inside a string that is already given and if it is then the program will print out the telephone next to that name. My code is as follows:
tilefwnikos_katalogos = "Christoforos 99111111: Eirini 99556677: Costas 99222222: George 99333333: Panayiotis 99444444: Katerina 96543217"
check=str(input("Give a name: "))
for check in tilefwnikos_katalogos:
if check=="Christoforos":
arxi=check.find("Christoforos")
elif check=="Eirini":
arxi=check.find("Eirini")
elif check=="Costas":
arxi=check.find("Costas")
elif check=="George":
arxi=check.find("George")
elif check=="Panayiotis":
arxi=check.find("Panayiotis")
elif check=="Katerina":
arxi=check.find("Katerina")
s=check.find(" ",arxi)
arxi=s
y=check.find(":",arxi)
telos=y
apotelesma=tilefwnikos_katalogos[arxi+1:telos]
print(apotelesma)
But when I try to run it, I input the name and then the following message pops up:
Traceback (most recent call last):
File "C:\Users\Sotiris\Desktop\test.py", line 16, in <module> s=check.find(" ",arxi)
NameError: name 'arxi' is not defined
What am I doing wrong?
You're getting your error because arxi isn't getting defined in the first place when then name the user gave is not present on your list.You can fix that by simply adding an unconditional else case to your if/else if bundle as pointed in the comments. But the very way you tackled this problem is faulty, storing data like this in a string is a bad idea, you want to use a dictionary:
phone_catalog = {'Christoforos': 99111111, 'Eirini': 99556677, 'Costas': 99222222, 'George':99333333, 'Panayiotis':99444444, 'Katerina': 96543217}
Also check isn't a very clear variable name, maybe you should try using something better like:
user_name = str(input("Give a name: "))
And now you can do your if/elif condition but replacing it for using dictionary logic and making sure you have a final else, like such:
if user_name in phone_catalog:
print(phone_catalog[user_name])
else:
print("Unknown user")
See how the dictionary made your life much easier and your code cleaner here? Read more on Python Data Structures.
so there are a few things you have overlooked / not going as expected, the first of which is how iterating over strings in python works:
tilefwnikos_katalogos = "Christoforos 99111111: Eirini 99556677: Costas 99222222: George 99333333: Panayiotis 99444444: Katerina 96543217"
for check in tilefwnikos_katalogos:
print(check)
#print(repr(check)) #this shows it as you would write it in code ('HI' instead of just HI)
so check can never be equal to any of the things you are checking it against, and without an else statement the variable arxi is never defined. I'm assuming you meant to use the check from the user input instead of the one in the loop but I'm not sure you need the loop at all:
tilefwnikos_katalogos = "Christoforos 99111111: Eirini 99556677: Costas 99222222: George 99333333: Panayiotis 99444444: Katerina 96543217"
check=str(input("Give a name: ")) #the str() isn't really necessary, it is already a str.
if check=="Christoforos":
arxi=check.find("Christoforos")
elif check=="Eirini":
arxi=check.find("Eirini")
elif check=="Costas":
arxi=check.find("Costas")
elif check=="George":
arxi=check.find("George")
elif check=="Panayiotis":
arxi=check.find("Panayiotis")
elif check=="Katerina":
arxi=check.find("Katerina")
else: raise NotImplementedError("need a case where input is invalid")
s=check.find(" ",arxi)
arxi=s
y=check.find(":",arxi)
telos=y
apotelesma=tilefwnikos_katalogos[arxi+1:telos]
print(apotelesma)
but you could also just see if check is a substring of tilefwnikos_katalogos and deal with other conditions:
if check.isalpha() and check in tilefwnikos_katalogos:
# ^ ^ see if check is within the string
# ^ make sure the input is all letters, don't want to accept number as input
arxi=check.find(check)
else:
raise NotImplementedError("need a case where input is invalid")
although this would make an input of C and t give Cristoforos' number since it retrieves the first occurrence of the letter. An alternative approach which includes the loop (but not calling the variable check!) would be to split up the string into a list:
tilefwnikos_katalogos = "..."
check = input(...)
for entry in tilefwnikos_katalogos.split(":"):
name, number = entry.strip().split(" ")
if check == name:
apotelesma=number
break
else:
raise NotImplementedError("need a case where input is invalid")
although if you are going to parse the string anyway and you may use the data more then once it would be even better to pack the data into a dict like #BernardMeurer suggested:
data = {}
for entry in tilefwnikos_katalogos.split(":"):
name, number = entry.strip().split(" ")
data[name] = number #maybe use int(number)?
if check in data:
apotelesma = data[check]
else:
raise NotImplementedError("need a case where input is invalid")
I'm currently working on a small text based game, the game remembers the gamestate based on global variables, for example, goblins_dead to see if you've killed the goblins yet.
This worked pretty well, until I decided to add a save and load function. The save function works, the load function does not, and while I know why, I can't come up with an easy fix.
The way the save function currently works is this, I have a list with all the global variables we've used in the game so far. Then I have the list run through each varaiable and give a 1 if its true or a 0 if its not, at the end it prints a "seed" that consists of a list of 1s and 0s the user can input. It looks like this, in my sample test code
def game_save():
print "This will give you a seed. Write it down, or see seed.txt"
print "When you start a new game, you will be propted to give your seed. Do so to reload."
global goblins_defeated
global lucky
global princesshelp
end = "done"
load_seed =[goblins_defeated, lucky, princesshelp, end]
load_seed.reverse()
variable = load_seed.pop()
seed = []
print globals()
while end in load_seed:
if variable == True:
seed.append("1")
print "APPENEDED 1"
print load_seed
variable = load_seed.pop()
elif variable == False:
seed.append("0")
print "APPENED 0"
print load_seed
variable = load_seed.pop()
else:
print "ERROR"
break
seedstring = ' '.join(seed)
print "This is your seed %s" %seedstring
This code works, it yields a string, that matches the values in the way I want.
The issue comes when its time to load. I inverted this process, like this:
def game_load():
print "Please type your seed in here:"
global goblins_defeated
global lucky
global princesshelp
end = "done"
seedlist = [goblins_defeated, lucky, princesshelp, end]
seed = raw_input("> ")
seed_list = seed.split(" ")
seed_value = seed_list.pop()
variable_list = [end, goblins_defeated, lucky, princesshelp]
variable = variable_list.pop()
testlist = []
while end in variable_list:
if seed_value == '1':
variable = True
print variable_list
print variable
print seed_value
elif seed_value == '0':
variable = False
print variable_list
print variable
print seed_value
else:
print "ERROR ERROR FALSE LOOP RESULT"
break
if bool(seed_list) == False:
print "List is empty"
else:
seed_value = seed_list.pop()
variable = variable_list.pop()
The mistake will be obvious to more seasoned programmers, it turns out lists load what a variable points at, not the variable name, so I can't assign things in this way.
This is where I'm stumped, I could just make a long list of if statements, but that's not very elegant. Further reading suggests that a dictionary approach might be the way to solve this, but I'm unsure on how I would go about implementing a dictionary, more specifically, I'm not sure how dictionaries interact with variables, my understanding is that this is how variables are actually stored in python, but I'm not sure how to get started on accessing and storing those variables reliably, or if I could use a global dictionary to store all my variables in the game properly. Basically, I'm unsure of how to "correctly" use a dictionary to its full potential, specifically how it interacts with variables.
That's much larger than necessary. Just use string formatting to provide the save password:
print 'Your seed is {}{}{}{}'.format(goblins_defeated+0, lucky+0, princesshelp+0, end+0)
Adding 0 converts each boolean into its numeric representation. Each value is inserted into the string, replacing the {}.
Load like this:
seed = raw_input("> ")
goblins_defeated, lucky, princesshelp, end = map(bool, map(int, seed.split()))
This splits seed on whitespace, maps each element to an integer, then maps each of those integers to a boolean, then unpacks that map object into the appropriate variables.
You don't necessarily have to store these conditions as booleans at all, as 1 and 0 will evaluate similarly, with 0 for False and 1 for True. Booleans are actually a subclass of int anyway. You can even do math with them, e.g. True+True equals 2.
I want to write a python program, first it asks you to enter two numbers, and then output all daffodil numbers between the two numbers, and it will continue run, until I enter a "q". I write a program, but it is wrong:
#coding=utf-8
while 1:
try:
x1=int(raw_input("please enter a number x1="))
x2=int(raw_input("please enter a number x2="))
except:
print("please enter only numbers")
continue
if x1>x2:
x1,x2=x2,x1
pass
for n in xrange(x1,x2):
i=n/100
j=n/10%10
k=n%10
if i*100+j*10+k==i+j**2+k**3:
print ("%-5d")%n
pass
Can somebody help? I think it should be simple, but I am not able to write it correctly.
I believe you've misunderstood the problem statement. Try this instead:
if i*100+j*10+k==i**3+j**3+k**3:
ref: http://en.wikipedia.org/wiki/Narcissistic_number
for n in xrange(x1,x2):
digits = map(int,str(n))
num_digits = len(digits)
if sum(map(lambda x:x**num_digits,digits)) == n:
print "%d is a magic number"%n
you will still have the issue of not being able to enter "q" since you force the input to be integers
I would like to address the quit event.
while True:
x1 = raw_input("please enter a number x1=")
x2 = raw_input("please enter a number x2=")
quit = ('q','Q')
if x1 in quit or x2 in quit:
break
else:
try:
x1, x2 = int(x1), int(x2)
except:
print("please enter only numbers")
continue
# The mathematical part... (for completeness) (not my code)
if x1>x2:
x1,x2=x2,x1
for n in xrange(x1,x2):
i=n/100
j=n/10%10
k=n%10
if i*100+j*10+k==i+j**2+k**3:
print "%-5d"%n
The pass statement is used only when you don't have anything to be executed in certain block of code. It does nothing more, so don't use it if not needed. It is there for the sake of the code looking clean & with correct indentation.
if some_thing: # don't do anything
else:
some_thing = some_thing_else
Note how the above if statement is syntactically incorrect. This is where pass comes handy. Say, you decide to write the if part later, till then you must provide pass.
if some_thing: # don't do anything
pass
else:
some_thing = some_thing_else
It's a bit tricky to know what's going on without more hints, but some issues I see right off:
You need to be consistent with indentation in Python. Your last if statement is less indented than statements above it (like the previous if and the for loop). This will cause an error. You're also using different amounts of indentation in other places, but since it's not inconsistent that's allowed (if a bad idea). Its usually best to pick one indentation standard (like four spaces) and stick with it. Often you can set your text editor to help you with this (turn on "Expand tabs to spaces" or something in the settings).
You've got two pass statements where they're unneeded or harmful. The first, after the line that has if x1>x2: x1,x2=x2,x1 is going to cause an error. You can't have an indented "suite" of code if you've put a series of simple statements on the end of your compound statement like an if. Either put the assignment on its own line, indented, or get rid of the pass. The last pass at the end of the code is not an error, just unnecessary.
You're missing a colon at the end of your try statement. Every statement in Python that introduces an indented suite ends with a colon, so it should be easy to learn where they're needed.
while True:
x1 = raw_input("please enter a number x1=")
x2 = raw_input("please enter a number x2=")
quit = ('q','Q')
if x1 in quit or x2 in quit:
break
else:
try:
x1, x2 = int(x1), int(x2)
except:
print("please enter only numbers")
continue
if x1>x2:
x1,x2=x2,x1
pass
for n in xrange(x1,x2):
i=n/100
j=n/10%10
k=n%10
if i*100+j*10+k==i+j**2+k**3:
print ("%-5d")%n
pass
i have it! thx to Ashish! it is exactly what i want! and i will quit wenn i enter q! thx a lot!