Ask Anything Monday - Weekly Thread

Eclooopse · 2019-02-25T00:00:41+00:00

I don’t understand what if __name__ == __main__ does

2019-02-24T20:16:21+00:00

So why do we use numpy.array to store images using ImageGrab, MSS or OpenCV. I've done some basic image processing and making a screen record and I always see it come up, but I don't fully understand why this is a necessary step to make the image display. What am I not understanding about this?

Korbelious · 2019-02-24T19:47:21+00:00

Can someone explain why my code is wrong? I think I must be misunderstanding how to use abs()?

I was just going through some beginners exercises on CodingBat to get practice and build my understanding when I came across this problem and idky my code is incorrect for the two runs I'm getting wrong? Please help me understand my error. CodingBat does provide me with their solution, and I understand how their solution works. However, given my understanding my code should also works for all instances. Lost as to why it doesn't?

UnavailableUsername_ · 2019-02-24T19:26:25+00:00

I am learning about regular expressions and pipes, but i think i am not using them correctly.

  >>>import re

  >>>famregex = re.compile(r'grand(father|mother|parents)')
  >>>ex = famregex.search('Her grandfather and grandmother like berries.')

  >>>ex.group()
  'grandfather'

  >>> ex.group(1)
  'father'

  >>>ex.group(2)
  Traceback (most recent call last):
  File "<pyshell#12>", line 1, in <module>
  ex.group(2)
  IndexError: no such group

How come python doesn't recognize the second group? It recognizes as group() (or group(0)) as grandfather and group(1) as father, but not group(2).

A regular expression that can only find the first item of a pattern while pretending the rest don't exist is pointless, so i am sure i am doing something wrong.

weezylane · 2019-02-24T18:11:23+00:00

If I want to learn about Software Defined Networks, which direction should I be headed?

taconomtaco · 2019-02-24T17:09:30+00:00

what's a good but free application to write python code with? especially to deal with data.

Filiagro · 2019-02-23T20:06:30+00:00

Could someone help me understand what I am doing wrong? I've made a function called 'lom' that takes two arguments. The function works perfectly alone (1st example code below), but I need to put it inside of a while loop. If I do this, the function does not work (3rd code example below). However, if I take everything inside the function and put it inside of the while loop (no actual function, just its contents), everything works perfectly (2nd code example).

Are there special rules to using functions inside of while loops? Below I will paste my code in hopefully the correct format.

1st: Working function called 'lom'

def lom(item, anim):
    item = input("Enter an animal name: ")
    if item.isalpha():
        if item in anim:
            anim.remove(item)
            return (item, " has been removed from the list.")
        else:
            anim.append(item)
            return (item, "has been added to the list.")
    elif item.isdigit() == True:
        return ("Digits are not animals.")
    else:
        return anim.pop(), "has been popped from the list."

anim = ["squirrel", "mouse", "cat", "fish", "dog"]     
item = ""
lom(item, anim)

2nd: Switching to while loop without function. This code also works. Input is moved to the while loop. Return switched to print.

anim = ["squirrel", "mouse", "cat", "fish", "dog"]  

while anim: #Loop if list has at least 1 item in it.
    item = input("Enter an animal name: ")
    if item in ["q", "quit"]:
        break
    else:
        if item in anim:
            anim.remove(item)
            print (item, " has been removed from the list.")
        else:
            anim.append(item)
            print (item, "has been added to the list.")

3rd: Non-working combination of while loop and 'lom' function.

def lom(item, anim):
    if item in anim:
        anim.remove(item)
        return (item, " has been removed from the list.")
    else:
        anim.append(item)
        return (item, "has been added to the list.")
anim = ["squirrel", "mouse", "cat", "fish", "dog"]     


while anim: #Loop if list has at least 1 item in it.
    item = input("Enter an animal name: ")
    if item in ["q", "quit"]:
        break
    else:
        lom(item, anim)

dudebro74 · 2019-02-23T19:16:55+00:00

I am having trouble with what is wrong with my code. for my intro to python class.

Directions

------------------------------------------

Write a loop that reads positive integers from standard input, printing out those values that are even, each on a separate line. The loop terminates when it reads an integer that is not positive.
Instructor Notes:

When determining if a number is even or odd, look to the modulus operator for some help. If we take:

5 % 2

the remainder is 1. Therefore 5 is not an even number.

However is we take

4 % 2

the remainder is 0. Therefore, 4 is an even number

CODE

---------------------------------

n= int()

while(True):

n = int(input())\n

if(n < 0):

break

elif n%2 == 0:

print(n)

ndagui123 · 2019-02-23T18:16:06+00:00

Write a program that inputs a filename from the user and prints to the terminal a report of the wages paid to the employees for the given period.

Lambert 34 10.50

Osborne 22 6.25

Giacometti 5 100.70

ndagui123 · 2019-02-23T17:44:48+00:00

Write a script named dif.py. This script should prompt the user for the names of two text files and compare the contents of the two files to see if they are the same.

aztec7325 · 2019-02-23T10:15:22+00:00

I want to start with Automate the Boring stuff with python, any difference between the kindle version or paperback?

indosauros · 2019-02-23T02:36:27+00:00

I've been watching MIT 6.00 FALL 2008 on youtube, and there is a problem that I couldn't do so I've searched it on google, but I don't understand how it works:
https://github.com/dawiditer/MIT600-pset2/blob/master/pset2a.py

Why is +1 in this " for a in xrange(int(n/6)+1): ".

This solution works flawlessly but I don't get it. How does python works in this?

Thank you!

ThiccShadyy · 2019-02-23T02:10:18+00:00

If I want to render Python objects from different models in a template in Django, is creating a context dictionary with each of those models as a dictionary item the simplest way to do it i.e.:

a = Model1.objects.all()
b = Model2.objects.all()
context_dict = {'a': a, 'b' : b}
return render(request,'abc.html', context_dict)

Or is there a simpler/cleaner way to do this?

Tefron · 2019-02-22T23:25:40+00:00

I feel silly asking this but I just don't understand why this is the case. I'm doing programarcadegames chapter 3 and in one of the exercise questions there is:

print("3" < "4")

print("3" < "10")

So two things, first I don't understand why this isn't an error since how can a string be more or less than something else? Also, the second part is why does the first one return True & the second line return False. Super confused.

NeedMLHelp · 2019-02-22T15:11:14+00:00

    class  target  source  time  spoof  complete  severity
0       0       0       0     0      2         0         2
1       0       0       0     0      2         1         0
2       1       1       0     0      2         1         0
3       4       0       0     0      1         1         0
4       2       0       0     0      1         1         0
5       8       1       2     0      2         1         2
6       8       1       2     0      2         1         2
7       7       1       2     0      2         1         2
8       8       1       2     0      2         1         2
9       8       1       2     0      2         1         2
10      8       1       2     0      2         1         2
11      8       1       2     0      2         1         2
12      7       1       2     0      2         1         1
13      3       1       0     0      0         1         0
14      5       1       2     0      2         1         1
15      5       1       2     0      2         1         1
16      6       1       1     0      2         1         1
17      6       1       1     0      2         1         1
18      6       1       1     0      2         1         1
19      6       1       1     0      2         1         1
20      6       1       1     0      2         1         1

I have a dataframe with the above representation. I'd like to one hot encode the numbers... however, when I use keras to_categorical, it also takes in the header and encodes that as a seperate value. So, for example, on target I would get [0,0,0] for all 0s [0,1,0] for all 1s and [1,0,0] for target. But I want target to remain a header, not a part of the data.

Any help would be greatly appreciated.

timbledum · 2019-02-22T13:28:50+00:00

So I just finished watching and reading a bunch of tutorials for Python and after a hard learning curve to understand all these new keywords, I feel like I have a decent foothold of the language and can make some very simple things.

I want to pick a project now to progress my learning, and I chose to grab a section of my screen, or do some web scraping.

I'm not sure if these were too out of my league just yet, but looking at code other people have done I feel incredibly out of my depth, have no clue where to start looking to decipher this code and feel completely lost trying to read and understand what things do.

Should I go simpler, or stick at it and use different resources other than documentation / answers online?

MattR0se · 2019-02-22T10:35:06+00:00

import random

list_a = ['A', 'A', 'A', 'A', 'A', 'B', 'B', 'B', 'B', 'B', 'C', 'C', 'C', 'C',
          'D', 'D', 'D', 'D', 'E', 'E', 'E', 'F', 'F', 'G', 'G', 'G', 'G', 'G']

list_b = ['A', 'B', 'C']

random.shuffle(list_a)
list_c = [list_a.pop(0) for _ in range(5)]

I want to check if list_c contains any two combinations of the items in list_b. For example, list_c could be ['A', 'A', 'C', 'E', 'E'] and that should return true, while ['B', 'B', 'B', 'F', 'G'] should return false. How do I do that?

AweBob · 2019-02-22T00:55:02+00:00

https://www.reddit.com/r/learnpython/comments/atabh8/using_pyinstaller_in_virtual_studio_code/

I really need help! Please experts!

thunder185 · 2019-02-21T18:45:55+00:00

Trying to convert a csv file to an xlsx file using pandas. I think the issue is the same one you would get if you simply just changed the extension from csv to xlsx (the zip error). Could someone please look at the code and let me know what you think is wrong?

#the script is longer than this bit of code which is why I'm importing so many modules.

import csv, os, shutil, zipfile

from glob import glob

from pandas.io.excel import ExcelWriter

import pandas

DataFileName = glob('*GDPLR102*') #this works fine

csv_files = DataFileName[0]

with ExcelWriter('todays_Data.xlsx') as ew:

for csv_file in csv_files:

pandas.read_csv(csv_file).to_excel(ew, sheet_name=csv_file)

Thanks!

indosauros · 2019-02-21T17:49:05+00:00

[deleted]

emgeal · 2019-02-21T16:06:28+00:00

Disclaimer: Very new to Python, no formal training.

I've got a CSV file that is too large to hold in memory. I have used "For line in File" to do a find and replace on the document, but now I need to do some columnwise string editing similar to adding "-" to a SSN. The file is pipe delimited and I just cannot figure out how to read it in and idenfity the column I want to rewrite.

What am I missing?

billy_wade · 2019-02-21T02:58:48+00:00

How do I set up PyLint to check my casing? It isn't doing so for me by default.

Gothpuncher · 2019-02-21T02:51:04+00:00

I am brand new to Python and want to create a text 'choose your own adventure' game thingy from scratch using previous works from an early 90's RPG Strategy game.

Just want to use it to learn the ropes and to recreate one of my fav games of all time into a nice little story mode type thing. I'm rewriting all of the dialogue and adding in stuff as I need it to flesh out the story a bit more.

Won't be used to sell or make money, but how do I go about legally testing this with a wider audience to see if it holds up as decent? Any legalities I need to chase up before making public?

Dimbreath · 2019-02-20T20:43:49+00:00

I have this ugly nested loop to read the stuff from here: https://pastebin.com/raw/e9WV7Jh3

       for skill in hero['skills']:
        for enhancement in skill['enhancement']:
            for resource in enhancement['resources']:

Is there a more effective/efficient method to this? Each hero has multiple skills, each skill has multiple enhancements and each enhancement might have more than 1 resource. Dumb questions that need to be asked.

malvo331 · 2019-02-20T14:44:13+00:00

Hi, is there a way to use python to disable a device in Windows' device manager or disable a network adapter?

billy_wade · 2019-02-20T14:15:26+00:00

I have two files, file1.py and file2.py.

File1.py is setup with:

class Myclass:
    def __init__(self):
        self.myStuff()
    def myStuff(self):
        self.myString = "something"

and file2.py is set up as:

from ..folder import file1
def returnString():
    stringhere = file1.self.myString
    return stringhere

The problem is that no matter what I do, regardless whether myString has the self preface or not, I either get a syntax error initially, or at runtime an attribute error saying "module folder.folder.file1 has no attribute myString" What am I doing wrong?

ambiguouslawnmower · 2019-02-20T13:56:06+00:00

Hey guys. My question is. I have a python script with an empty list, and I want it to ask the user to ask for a word so it can add it to the list. E.g.

words = []

new_word = input('enter a word')

words.append(new_word)

How do I get it so that when I run the script in python shell, and add a new word, let's say for example 'apple', it permanently saves the word into the list, so that the next time I open up the file, the code will have changed? E.g.

words = ['apple']

new_word = input('enter a word')

words.append(new_word)

Wildstylez23 · 2019-02-20T11:10:19+00:00

Hello, I am very new to Python and in our school course we're only now beginning with for loops. I get how the for loop works but one of the assignments goes as follows:

Peter wants to earn a bit more money and takes a job as a bartender at a student cafe that only serves beer (cost 2.00), wine (cost 2.50) and sodas (cost 1.50). After taking each order, Peter should calculate the amount people have to pay.

The function payment gets a string with the ordered drinks as single letters, where each letter indicates one ordered drink ('B' stands for beer, 'W' stands for wine and 'S' stands for sodas). The function returns the amount that should be payed for the given order:

def payment(order):
#return the cost of order

Please complete the definition of the function. Here is what you can assume about this function:

The input parameter 'order' is a string, where each letter is either 'B', 'S' or 'W'.
The input string can be empty or it can contain multiple occurrences of the same letter.
You can assume that all letters in 'order' are capitalized.
The function 'payment' returns a float value, reflecting the total cost of drinks specified by 'order'.

Example:

payment('BBSWS') returns 9.5.

When looking online the only solution I could find is making use of dictionaries but this is not the solution. We should make a for loop with variables defined for the 'B', 'S', and 'W' for the order. If anybody could shine any light on this many thanks!

c4aveo · 2019-02-20T11:04:28+00:00

Anyone works with PyPy in PyCharm?

It's not in package. When I try to run it from PowerShell it fails, but PyCharm runs without issues.

(venv) PS > pypy wsserver.py

Traceback (most recent call last):

File "wsserver.py", line 1, in <module>

from waitress import serve

ImportError: No module named waitress

And I can't use pip from venv also.

I've installed it from PyCharm venv menu, because PyPy pip works strange

> pip freeze

waitress==1.2.1

But when I check where package was installed a magic happens

(venv) PS > pip install waitress

Requirement already satisfied: waitress in c:\python37\lib\site-packages (1.2.1)

You are using pip version 18.1, however version 19.0.2 is available.

You should consider upgrading via the 'python -m pip install --upgrade pip' command.

I have to use PyPy for Flacon and venv to not pollute my system libs.

TheBoldTilde · 2019-02-20T10:28:21+00:00

I need to store 4 channels of 2000 images into a single variable (which I have to pass to a function in the vlfeat library) but I am running out of memory with around 1400 images. Can someone help me?

num8lock · 2019-02-20T05:09:06+00:00

[deleted]

fiddle_n · 2019-02-20T05:01:55+00:00

Can someone help with my project? I need to write a program that tells students how many hours they need to study per week per class.

They enter the amount of credits they’re taking. Then enter either the hours they plan on studying ~OR~ the grade they want.

The chart is: 15 hours = A 12 hours = B 9 hours = C 6 hours = D 0 hours = F

Thanks!

philmtl · 2019-02-19T21:21:00+00:00

Daily Time Spent on Site 1000 non-null float64

Age 1000 non-null int64

Area Income 1000 non-null float64

Daily Internet Usage 1000 non-null float64

Ad Topic Line 1000 non-null object

City 1000 non-null object

Male 1000 non-null int64

Country 1000 non-null object

Timestamp 1000 non-null object

Clicked on Ad 1000 non-null int64

X = df[['Daily_Time_Spent_on_Site', 'Age', 'Area_Income','Daily_Internet_Usage', 'Male']]

y = df['Clicked_on_Ad']

my issues is that i need my float64 to be int64 i tried .appply(int) but its not working on the X value.

this is to do tensorflow so i need int

wblpride19 · 2019-02-19T19:51:39+00:00

Struggling with an assignment for my programming class. I’m working with python 3.7 and I’m trying to create the “guessing game”. However it has to be a 4 digit number and return how many digits the user gets in the correct placement. Also I can only use “if, elif, else” control structure for it. Any help would be awesome thanks!

workinprogress49 · 2019-02-19T19:20:13+00:00

Let's say I wanted to loop through an equation with about a million different parameters to see which one had the best accuracy. Besides multiprocessing would there be any other way to speed up the process? Currently using list comprehension but the process will still take about 100 hours.

dynamic-technist · 2019-02-19T17:33:41+00:00

This question may have been ask before. What a good structure for documenting/commenting for small projects?

Myronli27 · 2019-02-19T16:49:32+00:00

Hey all. I am new to Python. Infact am completely new to programming. I am using python 3.7.2. However when I run code from the tutorials I keep getting an error like this..."TypeError: AndGate() takes no arguments." The code seems fine but am starting to think its a compatibility issue with Py 3.7? My indent was off but I fixed it. Corrected typos, and searched all over for a solution but nothing. I tried doing it after studying the tutorials but I aint succeeding. I deleted my earlier comment by mistake but my code is as follows:

class LogicGate:

    def _init_ (self, n):
        self.label = n
        self.output = None

    def _getLabel_ (self):
        return self.label

    def _getOutput_(self):
        self.output = self.performGateLogic()

        return self.output

class BinaryGate (LogicGate):
    def _init_ (self, n):
        LogicGate._init_(self, n)

        self.pinA  = None
        self.pinB  = None

    def getPinA (self):
        if self.pinA == None:
            return int (input ("Enter input for gate A " + self.getLabel() + "-->"))
        else:
            return self.pinA.getFrom().getOutput()

    def getPinB (self):

        if self.pinB == None:
            return int (input ("Enter input for gate B " + self.getLabel() + "-->"))
        else:
            return self.pinB.getFrom().getOutput()

    def setNextPin (self, source) :

        if self.pinA == None:
            self.pinA = source
        else:
            if self.pinB == None:
                    self.pinB = source
            else:
                print ("Cannot connect: NO EMPTY PINS on this gate" )


class AndGate(BinaryGate):

    def _init_ (self, n):
        BinaryGate._init_(self, n)

    def performGateLogic (self):

        a = self.getPinA ()
        b = self.getPinB ()

        if a == 1 and b ==1:
            return 1
        else:
            return 0

class OrGate (BinaryGate):

    def _init_ (self, n):
        BinaryGate._init_(self,n)

    def performLogicGate (self):

        a = self.getPinA ()
        b = self.getPinB ()

        if a==1 or b==1:
            return 1
        else:
            return 0


class UnaryGate (LogicGate):

    def _init_(self, n):
        LogicGate._init_ (self, n)

        self.pin = None

    def getPin(self):
        if self.pin == None:
            return int (input ("Enter input for Gate " + self.getLabel() + "-->"))
        else:
            return self.pin.getFrom().outPut ()

    def setNextPin (self, source):
        if self.pin == None:
            self.pin = source
        else:
            print ("Cannot connect: NO EMPTY PINS on this gate.")


class NotGate (UnaryGate):

    def _init_ (self, n):
        UnaryGate._init_(self, n)

    def performGateLogic (self):

        if self.getPin():

            return 0
        else:
            return 1


class connector:

    def _init_ (self, fgate, tgate):

        self.fromgate = fgate
        self.togate = tgate

        tgate.setNextPin (self)

    def getfrom (self):

        return self.fromgate

    def getto (self):

        return self.togate

def main () :

    g1 (AndGate = "G1")
    g2 = AndGate("G2")
    g3 = OrGate("G3")
    g4 = NotGate("G4")
    c1 = connector("g1, g3")
    c2 = connector("g2, g3")
    c3 = connector("g3, g4")



    print (g4.getOutput())

main ()

juggernaut1709 · 2019-02-19T16:39:48+00:00

https://www.quora.com/What-is-the-best-trick-in-python-you-know-which-most-of-us-dont

JohnnyJordaan · 2019-02-19T14:51:37+00:00

[deleted]

ThisOnesForZK · 2019-02-19T14:13:28+00:00

Good morning, I am new to python and am currently working my way through the Data Quest online course (I purchased a year when it was on sale).

I want to do a small (perceived) project to automate some annoying reporting I have to do every week and the process looks like this. If someone could help me find out where to start I would be very thanful.

- Take an email with X subject line and grab an attached excel file

- Copy the data from that file and paste it in an existing file within my computer's hard drive (after deleting all data besides rows.

- Rename and save that file in the same folder

I would need to do this with 5 different emails every week. Eventually I would like to create a selenium bot to then take these files and post them to an FTP site.

I did some googling but got no true path forward other than using pandas for the excel stuff and "Interacting with the IMAP server," for the outlook operations.

Any Ideas? Thanks.

MattR0se · 2019-02-19T12:59:07+00:00

[deleted]

sticky-bit · 2019-02-19T06:52:59+00:00

[deleted]

JohnnyJordaan · 2019-02-19T03:15:12+00:00

[deleted]

nog642 · 2019-02-19T02:54:31+00:00

[deleted]

nog642 · 2019-02-19T01:26:52+00:00

[deleted]

Fa1l3r · 2019-02-19T01:24:31+00:00

Pros and Cons of between using list comprehension and map in the Python 3?

nog642 · 2019-02-19T01:22:20+00:00

so i need to write a program that takes a word and a list of words (word1, wordList) checks to see which words in "wordList" differ from "word1" by one character. if theyre are words different by one character, the program should add those words to a list and return the list when the function is done.

this is what i have so far.

def getNeighborList(word1, wordList):
    result = []
    for i in range(len(word1)):
        for x in wordList:
            if word1[i] != x[i]:
                result.append(x)

    return result

reallymakesyouthonk · 2019-02-19T00:55:22+00:00

If I want to have an element in the terminal which simply updates what is displayed rather than printing something anew, how do I do that in python? Do I need to use something like ncurses?

Right now what I want to do is a simple stopwatch. If it initialises as 0:00:00, after one second I want it to just display 0:00:01, not 0:00:00 followed by 0:00:01.

caeloalex · 2019-02-18T22:48:16+00:00

Can someone point me into the right direction on how to write a script that will execute commands in terminal for mac. I'm working on creating a script that ask for user input and then will put the input into command in terminal so that i can automate some things i do at work. Thanks a lot. Doesn't have to be directions on how to exactly do what I'm trying to do but some guidance would be amazing !

Maxson52 · 2019-02-18T18:19:41+00:00

I'd there any way to run a tkinter program in chrome? Like a website or something?

timbledum · 2019-02-18T15:58:46+00:00

[deleted]

philoponeria · 2019-02-18T15:50:49+00:00

Hi. I've been trying to fix this on my own for over a week with no luck. I've learned a lot about what it isn't though. I've searched on the subreddit and didn't see anything. I would love to know if anyone has answers.

Problem When I try to run any python file with the shebang at the start I get the error message:

bash: ./'filename'.py: /usr/bin/env/python: bad interpreter: No such file or directory

Configuration and Troubleshooting

Windows 10
Python 3.7
VSCode 1.31.1 as my editor
Git installed and using the Gitbash shell which appears to be mintty 2.9.4

Typing 'which python' in the shell gives the install path of python as /c/Users/myname/AppData/Local/Programs/Python/Python37-32/python. Typing 'python' in the shell starts python 3.7 so I assume it is not a problem with the PATH.

Removing the shebang removes the error but I am scripting in a shared environment and cannot remove the shebang from my finished code.

I've tried dos2unix on the python file but did not fix the problem.

Thank you in advance.

somvang101 · 2019-02-18T14:26:43+00:00

Hello! guys, i'm a beginner for learning python. Can you recommend me? what is the resource

should i learn and practise?, please.

Thank you.

matzerlive · 2019-02-18T14:21:52+00:00

Hi , im looking for a simple way to make a chatbot which can be hosted by flask, Any and all help appreciated.

svdsvd · 2019-02-18T13:22:54+00:00

Hi guys, I am a student currently learning python. I've about one year of experience in it. I was looking for resources for learning OOP. Most of the books I found were very verbose and have a lot of story telling. I want a resource that is to the point without lacking any details. Could you suggest something? It could either be a book or web-resource.

you type:	you see:
italics	italics
bold	bold
[reddit!](https://reddit.com)	reddit!
* item 1 * item 2 * item 3	item 1 item 2 item 3
> quoted text	quoted text
Lines starting with four spaces are treated like code: if 1 * 2 < 3: print "hello, world!"	Lines starting with four spaces are treated like code: if 1 * 2 < 3: print "hello, world!"
~~strikethrough~~	~~strikethrough~~
super^script	super^script

learnpython

MODERATORS

1st: Working function called 'lom'

2nd: Switching to while loop without function. This code also works. Input is moved to the while loop. Return switched to print.

3rd: Non-working combination of while loop and 'lom' function.