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Python (Alternate two messages)

I have some code, and my goal is to make it so that when left button is clicked it will post text saying "Programming is fun!" and when it is pressed again, it will change that text to "It is fun to program", my idea was to make x = 0 if I wanted the first statement, and x = 1 if I wanted the second statement, but it keeps saying x is not defined, I've tried returning x but it simply won't... I've tried a variety of different methods but I can't figure it out. Thoughts? I'd like an alternative method to this, because I'm not sure that mine will work.
def text():
pf = Label(window2,text="Programming is fun")
pf.pack()
x = 0
def text2():
fp = Label(window2,text="It is fun to program")
fp.pack()
x = 1
def bt(event):
if x == 0:
text()
elif x == 1:
text2()
window2 = Tk()
window2.geometry("500x500")

The problem is that, in the scope of your functions, the variable x is indeed undefined.
An example:
height = 5
def some_function():
# code here can not access height just like that
When you want to access variables in functions, you generally have three options:
1) Put your code in a class instead. This requires some understanding of object oriented programming, and if you're a beginner this might not be the best choice for you
2) Pass the variable as an argument to the function and add it to the function's parameter list, for example like this:
def my_function(height):
# here height can be used
And when calling the function:
height_of_bob = 2
my_function(height_of_bob)
3) Use a global variable. This is usually not necessary, and is considered bad practice in general, but it will solve your problem just fine.

I found a way to do this below, the down low is that it's creating the text through that function, and then it's rebinding the key to do other function and then that function deletes previous text, creates the new text and then rebinds to the previous function, and the cycle continues. Here's the code.
def text(event):
global pf
fp.pack_forget()
pf = Label(window2,text="Programming is fun")
pf.pack()
window2.bind("<Button-1>", text2)
def text2(event):
global fp
pf.pack_forget()
fp = Label(window2,text="It is fun to program")
fp.pack()
window2.bind("<Button-1>", text)
window2 = Tk()
window2.geometry("500x500")
pf = Label(window2,text="Programming is fun")
fp = Label(window2,text="It is fun to program")
window2.bind("<Button-1>", text)

Creating Decision Tree for Simple Game

I am currently a new student learning python. This is my first real experience doing much computer coding. For my project I must create a fill in the blank quiz with three different levels of difficulty. Once the user chooses a difficulty the game should print a different paragraph based on the difficulty. Each section of the game works fine but I am having trouble creating the "difficulty chooser." No matter the difficulty I choose, the game rolls through the easy, medium, and the hard level in order and then crashes.
Below I have included the introductory text and the difficulty chooser. I would love some help. I am sure there are really obvious things I don't see. Thank you!
def introduction():
print '''Welcome to Kevin's European Geography Quizzes.
Test your knowledge of European geography. \n'''
difficulty = raw_input('''Do you want to play an easy, medium, or hard game?
Please type the number 1 for easy, 2 for medium, or 3 for hard.\n''' )
game_chooser(difficulty)
def game_chooser(difficulty):
cursor = 0
difficulty_choice = [easy_game(), medium_game(), hard_game()]
#each element of the above list links to a procedure and starts one of the
#mini-games.
while cursor < len(difficulty_choice):
if difficulty != cursor:
cursor += 1
else:
difficulty_choice[cursor]
break

You can do with if else if you only want to print something but if you have separate code block for each level then define a function for each level and use this pattern :
You can define the function blocks and call them basis on user input something like:
# define the function blocks
def hard():
print ("Hard mode code goes here.\n")
def medium():
print ("medium mode code goes here\n")
def easy():
print ("easy mode code goes here\n")
def lazy():
print ("i don't want to play\n")
# Now map the function to user input
difficulty_choice = {0 : hard,
1 : medium,
4 : lazy,
9 : easy,
}
user_input=int(input("which mode do you want to choose : \n press 0 for hard \n press 1 for medium \n press 4 for lazy \n press 9 for easy "))
difficulty_choice[user_input]()
Then invocation of function block will be:
difficulty_choice[num]()

Add a conditional for the input.
if difficulty == 'easy':
print("here is an easy game")
elif difficulty == 'medium':
print('here is a medium game')
elif difficulty == 'hard':
print('here is hard')
else:
print('Please enter valid input (easy, medium, hard)')
Under each if statement put your game code.

The reason your code goes through all the difficulties is because of this line:
difficulty_choice = [easy_game(), medium_game(), hard_game()]
When Python sees something like easy_game(), it calls the easy_game function and replaces it with the result. You don't want to call the function yet though, so you can take off the parenthesis to store just the function instead:
difficulty_choice = [easy_game, medium_game, hard_game]
This will mean you have to call the function after you take it out of the array.
As for the crash, when you use raw_input() you get a string back. That means when you type in the 1 to decide for an easy game, you get the character 1, which is represented by the number 49. That's why your code goes through everything and crashes: Your 1 is really a 49. In fact, if you type 1 < '1' into the interpreter, you'll get True back.
To fix that, you can pass the result of raw_input() to the int() function, which will parse it and give you the proper integer (or throw an exception if it can't be parsed). The last line of introduction would then look like game_chooser(int(difficulty)).
You could also skip most of the code of game_chooser by just indexing into the array (that's what they're for, after all):
def game_chooser(difficulty):
# the lack of parens here means you get the function itself, not what it returns
difficulty_choice = [easy_game, medium_game, hard_game]
#each element of the above list links to a procedure and starts one of the
#mini-games.
# note the parens to actually call the retrieved function now
difficulty_choice[difficulty]()

"else" statement executed before "if" statement after `undo` is used in Python

I have created the following function that allows the user to change the shape of the Python turtle to an image he/she selects from a file dialog file dialog that pops up when a specific button is pressed:
def TurtleShape(iop = None):
# "iop" is supposed to be an image path
try:
manipulateimage.config(state = NORMAL)
flipButton.config(state = NORMAL)
mirrorButton.config(state = NORMAL)
originalButton.config(state = NORMAL)
resetturtle.config(state = NORMAL)
rotateButton.config(state = NORMAL)
global klob
# The following "if-else" statement uses the "iop" argument's value as the value for "klob" if `iop` is NOT `None`
if iop != None:
klob = iop
print("lmcv")
else:
klob = filedialog.askopenfilename()
print("klobby")
global im
im = Image.open(klob)
pictures.append(im)
edited.clear()
print(im)
im.save(klob + '.gif', "GIF")
register_shape(klob + '.gif')
shape(klob + '.gif')
update()
except:
pass
The above function is also supposed to use the iop argument's value as the turtle's image if it is not None.
Now, consider this situation; you draw a bunch of things, set the turtle to an image, and just when you are about to stamp the image, you accidentally press the button that resets the turtle to its normal shape (yes, that button exists in my program). Oh no! How would you get it back without going through all the steps to open and edit it again? Well, that is where my undoHandler function (shown below) comes in. It just essentially undoes the last function called using many stacks, which I created as deques. It is pretty straightforward if you are proficient in Python:
def undoHandler():
if len(function) > 0 and draw.drawing == True:
undoHandler.handling = True
if not hasattr(undoHandler, "counter"):
undoHandler.counter = 0
undoHandler.counter += 1
# clear the canvas
Clear()
# Pop a point object from function deque
function.pop()
penup()
goto(-200, 100)
pendown()
try:
# Execute everything up to point before last function called
for i in function:
# Set canvas and turtle to previous state
tsd = i.recieveshape()
shape(tsd)
mndf = i.recieveheading()
setheading(mndf)
hk = i.getletterheight()
global letter_height
letter_height = hk
rk = i.getletterwidth()
global letter_width
letter_width = rk
milk = i.getspacewidth()
global space_width
space_width = milk
hw = i.getwidth()
width(hw)
op = i.getcolor()
try:
color(op)
except:
for g in colors:
cp = g.getcolor2()
colormode(255)
color(cp)
# Get function wrapped in Point object and execute it
j = i.getfunction()
j()
# Following is the code block where the issue occurs. Basically, if the function being run is equal to `TurtleShape`, then do the following...
if j.__name__ == "TurtleShape":
# `hfl` is a deque that holds all of the `pictures` deque's contents as it is cleared when the turtle is set to its default state
pictures.extend(hfl)
lmcv = pictures.pop()
pictures.append(lmcv)
try:
# Resize image to previous size if user changes it. Otherwise, skip this.
bun = picwidth.pop()
picwidth.append(bun)
mun = picheight.pop()
picheight.append(mun)
clob = lmcv.resize((int(bun), int(mun)), Image.ANTIALIAS)
except:
clob = lmcv
clob.save(klob + str(undoHandler.counter) + ".gif")
# Use the `clob.save` output from above as source image in `TurtleShape` function (this is where issue occurs)
TurtleShape(klob + str(undoHandler.counter) + ".gif")
print("Undone!")
else:
pass
except:
pass
Basically what happens here is that it takes the function (wrapped in a Point object) from a queue through which the main functions go through as they are called. The functions then get appended to the function deque, after which, when undoHandler is called by the user, the screen gets cleared, and latest value is popped from the function deque so that all the other actions except the last one will be executed again. This issue I am facing occurs specifically in the if j.__name__ == "TurtleShape": code block. Basically, for some reason, when the user chooses to undo the resetting of the turtle to its original shape, it works as it should until the TurtleShape function is executed by the undoHandler. For some reason, when the undoHandler executes the TurtleShape function, even when I give a valid argument for the iop attribute of the TurtleShape function (as you can see in the if j.__name__ == "TurtleShape": code block), the else statement is executed first (i.e. the file dialog comes up instead of continuing from the if statement). Only if the user clicks cancel in that dialog will the turtle get set to the previous image.
What is wrong in my code that is leading to this occurrence, and how would I stop this from happening? I have tried changing the klob attribute in the function where the output is saved in the undoHandler function to, for example, "SaveImage", but still no luck. I have also tried to add an if-elif statement in the TurtleShape when it is supposed to choose between iop or a file dialog as the value for klob, but still the issue occurs. Apparently, it executes the elif statement even when it is not necessarily true. Therefore, any help is very much appreciated in remedying this issue! :)

It's happening here:
j = i.getfunction()
j()
If the function you've just gotten is the TurtleShape() function, then you're calling it once with its default arguments (i.e., iop = None). Then you go into your big if j.__name__ == "TurtleShape": statement and call it again inside the if block.
Move that j() call into the else: block of your big if j.__name__ == "TurtleShape": statement, and your problem should go away.
Does that brief explanation make enough sense for you to understand why the problem is happening? Or do you need me to explain a bit more in-depth how calling j() is calling TurtleShape with the parameter iop = None?

Copy and paste Python functions in Emacs

I have a program that looks something like (this is a silly example to illustrate my point, what it does is not very important)
count = 0
def average(search_term):
average = 0
page = 0
current = download(search_term, page)
while current:
def add_up(downloaded):
results = downloaded.body.get_results()
count += len(results)
return sum(result.score for result in results)
total = average*count
total += add_up(current)
average = total/count
print('Average so far: {:2f}'.format(average))
page += 1
current = download(search_term, page)
If I have the cursor on any of the lines 8–11 and press a key combination I want Emacs to copy or kill the add_up function, and then I want to move the cursor to line 2 and press a key combination and paste the function there, with the correct level of indentation for the context it is pasted in.
Is this possible, and if so, how would I do that?

With python-mode.el py-kill-def and yank would do the job.
However, there are some restrictions. py-kill-def must be called from inside def in question. So needs to go upward from line 11 first.
Also indenting after insert poses some problems: as indent is syntax, sometimes Emacs can't know which indentation is wanted. In example below have an indent of 4 first and of 8 in add_up probably is not wanted - however it's legal code. After indenting first line in body of add_up, py-indent-and-forward should be convenient for the remaining.
def average(search_term):
average = 0
def add_up(downloaded):
results = downloaded.body.get_results()
count += len(results)
return sum(result.score for result in results)
page = 0
current = download(search_term, page)
while current:
total = average*count
total += add_up(current)
average = total/count
print('Average so far: {:2f}'.format(average))
page += 1
current = download(search_term, page)

For this type of thing I usually use expand-region, which I choose to bind to C-=.
Using your example I can select the add_up() function by pressing C-= once, kill the region normally (C-k), move to line 2, and yank as usual (C-y).
Depending on what else you have configured for Python you may have to clean up some whitespace, or it may get cleaned up for you. For example, aggressive-indent would be helpful.
One manual option would be to reindent the pasted code with something like C-x C-x M-\.

I've been using smart-shift (available in Melpa) for this sort of thing. global-smart-shift-mode to enable (beware, it binds keys). Select the block you want to move (I'd use expand-region like Chris), and the default keybind C-S-c <arrow> starts moving it. Once you're shifting, the arrows (without C-S-c) shift further. Horizontal shifts use the major mode's indent offset (python-indent-offset for python.el).

Endless loop wont work

I'm having difficulty realizing why is this part of code
for stanje in pomocna:
for znak in abcd:
novi = tablicaPrijelaza.get((stanje, znak))
dohvatljiva_stanja.append(novi)
dohvatljiva_stanja = list(set(dohvatljiva_stanja))
dohvatljiva_stanja = sorted(dohvatljiva_stanja)
pomocna = dohvatljiva_stanja
not done x times with this implementation of a for that does x iterrations
Yet it seems that it does an endless loop.
One iterration is fine and does what it is supposed to, but after first iterration it goes nowhere
Traceback says it is stuck in second append.

Proper implementation is something more like this which works:
for stanje in dohvatljiva_stanja:
for znak in abcd:
novi=tablicaPrijelaza.get((stanje,znak))
if novi:
pomocna.append(novi)
dohvatljiva_stanja.extend(pomocna)
dohvatljiva_stanja=list(set(dohvatljiva_stanja))
dohvatljiva_stanja=sorted(dohvatljiva_stanja)
del pomocna[0:len(pomocna)]