que = queue.Queue()
get_videos(que)
def get_videos(self, theQue):
links = input('Enter links comma seperated: ')
list = links.split(',')
for i in list:
theQue.put(i)
return
My current code says "NameError get_videos is not defined"
I guess I tried with and without self and neither help maybe I'm confused how this works.
You are calling the function before its definition, the interpreter has no clue what get_videos you are talking about or trying to call here, so you need to call it after it's defined
que = queue.Queue()
def get_videos(theQue):
links = input('Enter links comma seperated: ')
list = links.split(',')
for i in list:
theQue.put(i)
return
get_videos(que)
Also self param is only for class methods, you could name your parameters anything you want, but you are passing only one value, the self gets passed automatically when you call this function on a class instance -it should be defined within the class-
You should write like that:
def get_videos(self, theQue):
links = input('Enter links comma seperated: ')
list = links.split(',')
for i in list:
theQue.put(i)
return
que = queue.Queue()
get_videos(que)
Related
I'm trying to learn OOP but I'm getting very confused with how I'm supposed to run the methods or return values. In the following code I want to run read_chapters() first, then sendData() with some string content that comes from read_chapters(). Some of the solutions I found did not use __init__ but I want to use it (just to see/learn how i can use them).
How do I run them? Without using __init__, why do you only return 'self'?
import datetime
class PrinceMail:
def __init__(self):
self.date2 = datetime.date(2020, 2, 6)
self.date1 = datetime.date.today()
self.days = (self.date1 - self.date2).days
self.file = 'The_Name.txt'
self.chapter = '' # Not sure if it would be better if i initialize chapter here-
# or if i can just use a normal variable later
def read_chapters(self):
with open(self.file, 'r') as book:
content = book.readlines()
indexes = [x for x in range(len(content)) if 'CHAPTER' in content[x]]
indexes = indexes[self.days:]
heading = content[indexes[0]]
try:
for i in (content[indexes[0]:indexes[1]]):
self.chapter += i # can i use normal var and return that instead?
print(self.chapter)
except IndexError:
for i in (content[indexes[0]:]):
self.chapter += i
print(self.chapter)
return self????? # what am i supposed to return? i want to return chapter
# The print works here but returns nothing.
# sendData has to run after readChapters automatically
def sendData(self):
pass
#i want to get the chapter into this and do something with it
def run(self):
self.read_chapters().sendData()
# I tried this method but it doesn't work for sendData
# Is there anyother way to run the two methods?
obj = PrinceMail()
print(obj.run())
#This is kinda confusing as well
Chaining methods is just a way to shorten this code:
temp = self.read_chapters()
temp.sendData()
So, whatever is returned by read_chapters has to have the method sendData. You should put whatever you want to return in read_chapters in a field of the object itself (aka self) in order to use it after chaining.
First of all, __init__ has nothing to do with what you want to achieve here. You can consider it as a constructor for other languages, this is the first function that is called when you create an object of the class.
Now to answer your question, if I am correct you just want to use the output of read_chapters in sendData. One of the way you can do that is by making the read_chapters a private method (that is if you don't want it to use through the object) using __ in the starting of the name like __read_chapters then make a call to the function inside the sendData function.
Another point to consider here is, when you are using self and don't intend to use the function through the object you don't need to return anything. self assigns the value to the attribute of the current instance. So, you can leave the function read_chapters at self.chapter = i and access the same in sendData.
Ex -
def sendData(self):
print(self.chapter)
I'm not an expert but, the reason to return self is because it is the instance of the class you're working with and that's what allows you to chain methods.
For what you're trying to do, method chaining doesn't seem to be the best approach. You want to sendData() for each iteration of the loop in read_chapters()? (you have self.chapter = i which is always overwritten)
Instead, you can store the chapters in a list and send it after all the processing.
Also, and I don't know if this is a good practice but, you can have a getter to return the data if you want to do something different with (return self.chapter instead of self)
I'd change your code for:
import datetime
class PrinceMail:
def __init__(self):
self.date2 = datetime.date(2020, 2, 6)
self.date1 = datetime.date.today()
self.days = (self.date1 - self.date2).days
self.file = 'The_Name.txt'
self.chapter = []
def read_chapters(self):
with open(self.file, 'r') as book:
content = book.readlines()
indexes = [x for x in range(len(content)) if 'CHAPTER' in content[x]]
indexes = indexes[self.days:]
heading = content[indexes[0]]
try:
for i in (content[indexes[0]:indexes[1]]):
self.chapter.append(i)
except IndexError:
#not shure what you want to do here
for i in (content[indexes[0]:]):
self.chapter.append(i)
return self
# sendData has to run after readChapters automatically
def sendData(self):
pass
#do what ever with self.chapter
def get_raw_chapters(self):
return self.chapter
Also, check PEP 8 Style Guide for naming conventions (https://www.python.org/dev/peps/pep-0008/#function-and-variable-names)
More reading in
Method chaining - why is it a good practice, or not?
What __init__ and self do on Python?
I have a method object with assigned value from user's input inside a class. The problem is i can't use the method object maxcount_inventory = int(input("How many Inventories: ")) outside the class. The error says "method' object cannot be interpreted as an integer"
class CLASS_INVENTORY:
maxcount_inventory = int(input("How many Inventories: "))
inventory_name = []
def __init__(Function_Inventory):
for count_inventory in range(Function_Inventory.maxcount_inventory):
add_inventory = str(input("Enter Inventory #%d: " % (count_inventory+1)))
Function_Inventory.inventory_name.append(add_inventory)
def Return_Inventory(Function_Inventory):
return Function_Inventory.inventory_name
def Return_Maxcount(Function_Inventory):
return maxcount_inventory
maxcount_inventory = CLASS_INVENTORY().Return_Maxcount
Another extra question if I may, how can i access items in the list per index outside the class? I have the code below, but I think it's not working. Haven't found out yet due to my error above.
for count_inventory in range(maxcount_inventory):
class_inv = CLASS_INVENTORY().Return_Inventory[count_inventory]
print(class_inv)
skip()
Here is my full code: https://pastebin.com/crnayXYy
Here you go I've refactored your code.
As #Daniel Roseman mentioned you should be using self rather than Function_Inventory, so I changed that. I also changed the return value of Return_Maxcount to provide a list as you requested.
class CLASS_INVENTORY:
maxcount_inventory = int(input("How many Inventories: "))
inventory_name = []
def __init__(self):
for count_inventory in range(self.maxcount_inventory):
add_inventory = str(input("Enter Inventory #%d: " % (count_inventory+1)))
self.inventory_name.append(add_inventory)
def Return_Inventory(self):
for item in self.inventory_name:
print(item)
def Return_Maxcount(self):
return self.inventory_name
maxcount_inventory = CLASS_INVENTORY()
inventory_list = maxcount_inventory.Return_Maxcount()
maxcount_inventory.Return_Inventory()
You can change the print statement at the bottom and set that equal to a variable to access it outside of the class itself.
In your code just change this:
maxcount_inventory = CLASS_INVENTORY().Return_Maxcount
to this:
maxcount_inventory = CLASS_INVENTORY().Return_Maxcount()
also change the variables in your class to have the self. prefix before them
like self.maxcount_inventory
the reason is you want to call your method , otherwise it will try getting a variable not the method.
you also want to change all your arguments in your functions inside of the class to self
I am new to programming and self taught. I have used Stack Exchange to find answers to many of my questions without ever needing to ask (it is a great community), but I cannot seem to find the answer to this anywhere. I apologize if this is a duplicate.
I am trying to assign a method to a variable, but I want to save it to a text file for access later. I am using open() to access the text file and eval() to change it from a string when loading the information. I just cannot figure out how to do the opposite.
from random import randint
class Example (object):
def __init__(self):
self.name = ""
self.lucky_number = ""
def create_person(self):
self.name = input("What is your name?")
self.lucky_number = randint(1,10)
save_person = [self.name, self.lucky_number]
with open("example.txt", "w") as f:
for i in save_person:
f.write(i + '\n')
def load_person(self):
with open("example.txt", 'r') as f:
person_list = f.readlines()
if len(person_list) <= 1:
create_person()
else:
self.name = person_list[0].strip('\n')
self.lucky_number = eval(person_list[1].strip('\n'))
person = Example()
person.load_person()
I want to keep the randint(1,10) part because I want to reuse the function, but I may change the value to something else later depending on user selection (such as changing self.lucky_number = randint(1,10) to self.lucky_number = randint(1,30)).
I know I can just change it to self.lucky_number = randint(1,var) and then save the value of var instead, but it made me wonder if the way I'm trying is possible.
Thanks in advance for any assistance. I am using Python 3.5.
Edit: For clarification I am looking to store the actual function, i.e. randint(1,10), in the text file, not the value of the function.
EDIT 2: I am going to close this as answered because I found a way to do what I needed, but it is not a direct way.
I was able to find a way to accomplish what I was looking for, but it is a roundabout way. I changed the call to the function into a string, then created a new class variable that calls the variable with the function string. The other class variable meant to run the function now has eval() around it and calls the new class variable I created. I save the new class variable instead.
from random import randint
# Now a string instead of a function call
prog = "randint(1,10)"
class Example (object):
def __init__(self):
self.name = ""
"""Added self.temp to grab the string from outer
variable and will change self.temp to get the desired
functions as strings"""
self.temp = prog
"""self.lucky_number grabs new class variable and
eval() turns it into callable function"""
self.lucky_number = eval(self.temp)
def create_person(self):
self.name = input("What is your name?")
self.temp = prog
self.lucky_number = eval(self.temp)
""" Saves new class variable now and stores actual
function, eg randint(1,10)"""
save_person = [self.name, self.temp]
with open("example.txt", "w") as f:
for i in save_person:
f.write(str(i) + '\n')
def load_person(self):
with open("example.txt", 'r') as f:
person_list = f.readlines()
if len(person_list) <= 1:
self.create_person()
else:
self.name = person_list[0].strip('\n')
self.temp = person_list[1].strip('\n')
person = Example()
person.load_person()
Its roundabout, but gets the job done. I can change self.temp to whatever variable (formatted properly) I need and the code will work. If anyone can think of a direct way please let me know.
This question already has answers here:
How can I call a function within a class?
(2 answers)
Closed 6 years ago.
I wanted to call the function spider which is within a class with the parameters such as url,word and maxPages.
when I try calling it the following way I get an error because spider() gets more than 3 arguments (it gets 4 arguments instead).
Please can someone guide me as to how I can call the function which is within a class correctly.
My code looks like this:
import HTMLParser
from urllib2 import urlopen
from pandas.io.parsers import TextParser
class LinkParser(HTMLParser.HTMLParser):
#other methods
def spider(url,word,maxPages):
pagesTovisit = [url]
numberVisited=0
foundWord = False
maxPages = 0
while numberVisited < maxPages and pagesTovisit != [] and not foundWord:
numberVisited = numberVisited +1
url = pagesTovisit[0]
pagesTovisit = pagesTovisit[1:]
try:
print numberVisited, "Visiting:", url
parser = LinkParser()
data, links = parser.getLinks(url)
if data.find(word)>-1:
foundWord = True
pagesTovisit = pagesTovisit +links
print "Success"
except:
print "failed"
if foundWord:
print "the word",word,"was found at",url
else:
print "word not found"
url = raw_input("enter the url: ")
word = raw_input("enter the word to search for: ")
maxPages = raw_input("the max pages you want to search in for are: ")
lp=LinkParser()
lp.spider(url,word,maxPages)
Your indentation in the post is all wrong but I assume spider is in the class. You need to add the self keyword as first argument to the function to make it a method:
class LinkParser(HTMLParser.HTMLParser):
def spider(self,url,word,maxPages):
...
Inside your spider method there is a call to LinkParser.getLinks(). Instead of creating another instance of the class you should call the method by: self.getLinks(...) as this won't create new instances.
Also class methods and members can be reached inside methods by writing:
def methodOfClass(self,additionalArguments):
self.memberName
self.methodName(methodArguments)
Ignoring the indentation errors which I believe are only copy-paste issues
Every method in Python implicitly recieves the instance it is called upon as the first argument, so its definition should count for that.
Change def spider(url, word, maxPages) to def spider(self, url, word, maxPages).
Am new to Python OOP. Please dont be harsh. Here is my code which calculates which is the fastest time of an athlete from a list and displays them. But When Running, I get this error:
z= add.mylist.min()
NameError: global name 'add' is not defined
My Code:
class Athlete:
def add(self):
list=[]
mylist=[]
for i in range(2):
self.name = raw_input("Enter name: ")
self.fastest_time = input("time: ")
list.append(self.name)
mylist.append(self.fastest_time)
print "Names: ",list
print "Fastest times: ",mylist
def display(self):
z= add.mylist.min()
w= add.mylist.index(z)
print "Minimum time: ",z
print "Name of athelte with fastest time: ",list[w]
x = Athlete()
x.add()
x.display()
You need to refer to methods on the instance with the self parameter. In addition, your add() method needs to return the mylist variable it generates, you cannot refer to method local variables as attributes on methods:
def display(self):
mylist = self.add()
z = min(mylist)
w = mylist.index(z)
def add(self):
list=[]
mylist=[]
for i in range(2):
self.name = raw_input("Enter name: ")
self.fastest_time = input("time: ")
list.append(self.name)
mylist.append(self.fastest_time)
print "Names: ",list
print "Fastest times: ",mylist
return mylist
That is what self is for, as a reference point to find instance attributes and other methods on the same object.
You may want to rename list to something that does not shadow the built-in type.
Martijn has already answered your question, so here are some remarks and code style tips:
New-style classes derive from object
You have both athlete names and their times, those belong together as key-value pairs in a dictionary instead of two separate lists
Don't use print statements inside class methods, a class method should return an object that you then can print
what if you have more then 2 athletes for which you want to enter the time? If you make the number of athletes an argument of your function, you can add a variable number of athlethes
give descriptive variable names (not mylist) and don't use names of builtin functions (like list) as variable name
variables that you want to use throughout your class can be initalized in an __init__method.
For printing, use the format function instead of using commas
use if __name__ == '__main__' so that your Python file can act as either reusable modules or as standalone program
Taking these into account, I would rewrite your code to something like this:
from collections import defaultdict
class Athlete(object): # see (1)
def __init__(self): # see (6)
self.athlete_times = defaultdict(str) # see (2)
def add_athletes_and_times(self, n): # see (4)
for i in range(n):
self.name = raw_input("Enter name: ")
self.fastest_time = input("time (in seconds): ")
self.athlete_times[self.fastest_time] = self.name
def get_fastest_time(self):
return min(self.athlete_times) # see (3)
if __name__ == '__main__': # see (8)
x = Athlete()
x.add_athletes_and_times(2)
for fast_time in x.athlete_times:
print "The fastest time of athlete {0} is {1} seconds.".format(
x.athlete_times[fast_time], fast_time) # see (7)
fastest_time = x.get_fastest_time()
print "The overall fastest time is: {0} seconds for athlete {1}.".format(
fastest_time, x.athlete_times[fastest_time])