onionradish posted:

Unrelated to your issue, but something to be aware of because things like this can really bite you in the butt later:

If you use "map" as a variable name, you are overwriting the built-in Python function "map" with your data. You variable will work, but the function won't, and it won't be obvious why code that uses that function looks like it should be working but isn't.

You're probably not using the "map" function in your script and may not need to, but it's a good habit to avoid using Python reserved words as variables. Otherwise, it's really easy to accidentally write things like "list = [1,2,3]" or "type = 'mountains'" or "range = 10".

You *can* use reserved words as class attribute names like "self.map[x][y]" in the example from SurgicalOntologist below, because they're attached to the object.

PyCharm was invaluable when I was learning because it flagged that kind of stuff.

quote:

Origins and order
=================

What do we know about Professor Boolean's past? It's mostly rumor and conjecture, but a few things are known to be true.

Mad Professor Boolean wasn't always a super villain. Early in his career, he was an average paper pusher, working in an office with some very backwards technology. One of his primary jobs was to carry date cards between departments. One morning, he tripped over a unicycle and dropped his date cards on the floor. He hit his head - and hit upon the idea of breeding an army of zombie rabbits to do his bidding and manage simple tasks. But that comes later. Before he could quit with an explosive YouTube video, the professor had to get his cards back in order.

Aha! It seems he recorded the details of this life-changing event in his diary. Let's try to reproduce his methods:

The goal is to get the date cards back in order. Each set of date cards consists of 3 cards, each with a number written on it. When arranged in some order, the numbers make up the representation of a date, in the form month/day/year. However, sometimes multiple representations will be possible. For example, if the date cards read 1, 1, 99 it could only mean 01/01/99, but if the date cards read 2, 30, 3, it could mean any one of 02/03/30, 03/02/30, or 03/30/02.

Write a function called answer(x, y, z) that takes as input the 3 numbers on the date cards. You may assume that at least one valid representation of a date can be constructed from the cards.

If there is only one valid representation, the function should return it as a string, in the form MM/DD/YY. If there are multiple valid representations, the function should return the string "Ambiguous." Each of x, y, z will be between 1 to 99 inclusive. You may also assume that there are no leap years.

Languages
=========

To provide a Python solution, edit solution.py
To provide a Java solution, edit solution.java

Test cases
==========

Inputs:
(int) x = 19
(int) y = 19
(int) z = 3
Output:
(string) "03/19/19"

Inputs:
(int) x = 2
(int) y = 30
(int) z = 3
Output:
(string) "Ambiguous"

Use verify [file] to test your solution and see how it does. When you are finished editing your code, use submit [file] to submit your answer. If your solution passes the test cases, it will be removed from your home folder.

Begall posted:

Is there a solution much cleaner than this? Is there any decent publicly available page with teasers like these?

supercrooky posted:

Python code:

def answer(x, y, z):
    month_length = {1: 31, 2: 28, 3: 31, 4: 30, 5: 31, 6:30, 7: 31, 8: 31, 9: 30, 10: 31, 11: 30, 12: 31}
    date = tuple(sorted((x, y, z)))
    if (date[1] <= 12 and date[0] != date[1]) or (date[2] <= month_length[date[0]] and date[1] != date[2]):
        return "Ambiguous"
    else:
        return "%02d/%02d/%02d" % date

Dominoes posted:

Any things that can cause sorted() not to work as expected?

Python code:

 x = [{'std_low': 1.0,
  'conv_thresh': -0.1,
  'profit': 0.0079000000000000008,
  'sell_days': 6,
  'std_high': 2.5},
 {'std_low': 1.0,
  'conv_thresh': -0.1,
  'profit': nan,
  'sell_days': 6,
  'std_high': 3.0},
 {'std_low': 1.5,
  'conv_thresh': -0.1,
  'profit': 0.0038999999999999998,
  'sell_days': 6,
  'std_high': 2.5},
 {'std_low': 1.5,
  'conv_thresh': -0.1,
  'profit': nan,
  'sell_days': 6,
  'std_high': 3.0},
 {'std_low': 1.0,
  'conv_thresh': -0.09,
  'profit': 0.0079000000000000008,
  'sell_days': 6,
  'std_high': 2.5}]

[{'std_low': 1.0,
  'conv_thresh': -0.1,
  'profit': 0.0079000000000000008,
  'sell_days': 6,
  'std_high': 2.5},
 {'std_low': 1.0,
  'conv_thresh': -0.1,
  'profit': nan,
  'sell_days': 6,
  'std_high': 3.0},
 {'std_low': 1.5,
  'conv_thresh': -0.1,
  'profit': 0.0038999999999999998,
  'sell_days': 6,
  'std_high': 2.5},
 {'std_low': 1.5,
  'conv_thresh': -0.1,
  'profit': nan,
  'sell_days': 6,
  'std_high': 3.0},
 {'std_low': 1.0,
  'conv_thresh': -0.09,
  'profit': 0.0079000000000000008,
  'sell_days': 6,
  'std_high': 2.5}]

Same if I use operator.itemgetter() for the key. What's up? I suspect it has something to do with floats being weird sometimes. I don't think it's the numpy.nan thing, since it still doesn't work with those entries removed.

This works as expected:

Python code:

In [38]: x  = [{'v': 4}, {'v': 2}, {'v': 99}, {'v': np.nan}]

In [39]: sorted(x, key=lambda i: i['v'])
Out[39]: [{'v': 2}, {'v': 4}, {'v': 99}, {'v': nan}]

Looks like if I replace the profit values manually with ones that didn't get hosed by round(), it works. So, chalking this up to floats being weird.

superstepa posted:

What would be the easiest way to run a periodic (once every 24 hours) task within a flask app. It's literally 3 lines of code so I wouldn't want to use something advanced like celery

EAT THE EGGS RICOLA posted:

What are you trying to do? If it's something super simple I'd probably just set up a cron job.

Thermopyle posted:

I just wanted to stop in and say that I've been using mypy for the last week (I've just played with it previously) and it's pretty super if you've thought that Python could use option static type checking.

I won't use it all the time, but for larger programs its pretty nice (well it's still experimental so I won't use it for larger programs either yet).

Thermopyle posted:

I just wanted to stop in and say that I've been using mypy for the last week (I've just played with it previously) and it's pretty super if you've thought that Python could use option static type checking.

I won't use it all the time, but for larger programs its pretty nice (well it's still experimental so I won't use it for larger programs either yet).

Dominoes posted:

I like how the type signatures provide a quick insight of what the function's doing. It's especially useful when inputting or outputting complex/nested data structures.

supermikhail posted:

I've tried to post this question multiple times, but it seemed like I came up with a new possible solution every time. I guess now I've diluted it to the essentials.

Do I have to do this?

code:

    @staticmethod
    def check(problem, answer):
        OneOperandProblem.check(problem, answer)
        answer = Decimal(str(answer))
        dec_places = -answer.as_tuple().exponent
        print("Decimal places: " + str(dec_places))
        correct = Decimal(str(round(sqrt(problem), dec_places)))
        print("Correct solution: " + str(correct))
        print("Submitted answer: " + str(answer))
        if answer == correct:
            return True
        else:
            return False

I'm referring to the numerous 'Decimal(str(' expressions. Otherwise it refuses to work. A possible input would be (80, 8.94), and as I've determined, the omission of any 'Decimal(str(' expression returns False, while it should be True. Also, I thought 'answer' came in from the calling method as a Decimal, because that's what it is there, but apparently no.

A similar method in a different place seems to work a little simpler:

code:

    @staticmethod
    def check(problem, answer):
        TwoOperandProblem.check(problem, answer)
        dec_places = -Decimal(str(answer)).as_tuple().exponent
        print("decimal places: " + str(dec_places))
        correct = round(Decimal(problem[0]) / problem[1], dec_places)
        print("correct answer: " + str(correct))
        if answer == correct:
            return True
        else:
            return False

But in the first method putting Decimal anywhere except around the whole expression doesn't seem to work. Sort of strange because I'd think it's the output of 'round' as a float which would be the problem. Although, I don't even have to convert 'answer' to Decimal for the comparison. Maybe I haven't tested it enough? drat. Okay, I'm going to post it now because it's late at night, and if you think I should do it, I'll retest the second method tomorrow.

quote:

Do I have to do this?

code:

    @staticmethod
    def check(problem, answer):
        OneOperandProblem.check(problem, answer)
        answer = Decimal(str(answer))
        dec_places = -answer.as_tuple().exponent
        print("Decimal places: " + str(dec_places))
        correct = Decimal(str(round(sqrt(problem), dec_places)))
        print("Correct solution: " + str(correct))
        print("Submitted answer: " + str(answer))
        if answer == correct:
            return True
        else:
            return False

I'm referring to the numerous 'Decimal(str(' expressions. Otherwise it refuses to work. A possible input would be (80, 8.94), and as I've determined, the omission of any 'Decimal(str(' expression returns False, while it should be True. Also, I thought 'answer' came in from the calling method as a Decimal, because that's what it is there, but apparently no.

Rlazgoth posted:

I am currently working on my first programming project ever, which is a tool for mining academic databases and automatically storing search matches in a local .txt file for later processing. I have no previous experience in programming whatsoever but after a LOT of reading and watching tutorials I managed to get an initial version of the script working. The script is very short and simple, but I will have to build a GUI for it since the potential users will very likely have no proficiency in programming.

I have made some attempts at creating a GUI with Tkinter, but I'm finding it much more difficult to program than the main script. Is there an easier and faster way to build GUIs? What I'm attempting to create is akin to search form, with several search bars (the number of which is defined by the user), with a dropdown menu for search type besides each of them (e.g, "Topic", "Author", etc.), and another for boolean operators.

KICK BAMA KICK posted:

Whatever GUI library you use (seconding Dominoes) the most important thing is structuring your code to separate the user interface from the logic. Not doing that will bite you in the rear end the second you realize you need to refactor something. There's a few different patterns like MVC and MVP that you can implement to satisfy this but don't get hung up on which, just pick something that makes sense to you.

Also, totally cool if you're just doing this to learn to code but just in case: is there something specific about your domain that makes writing a custom program a better solution to a problem that sounds like "search some databases" than just marshaling your data into a format usable by any of the myriad general-purpose database applications?

QuarkJets posted:

Also, if you pass 80, 8.94 to either of the methods shown here, then the lines that looks like this:

code:

OneOperandProblem.check(problem, answer)

don't actually accomplish anything because you're not catching any output. The "answer" variable within the scope of your check() method is not being modified by OneOperandProblem.check().

QuarkJets posted:

It'd be useful if we knew what we were looking at here. Can you show us an entire class definition?

supermikhail posted:

That could well be a newbie thing, but that checks that 'problem' and 'answer' are valid. OneOperandProblem is the superclass of several classes, each of which requires this operation (I think).

For clarity:

code:

class OneOperandProblem(Problem):
...
    @staticmethod
    def check(problem, answer):
        if type(problem) is not int or not issubclass(type(answer), Number):
            raise TypeError

quote:

I don't think the entire class is going to be useful. It's a bunch of static methods which don't interact with each other. The one supremely confusing thing that I failed to clarify yesterday is above, and the class's name is RootProblem, so the idea of the method is to check that 'answer' is the correct root for the 'problem'. 'problem' is an int, by the way.

drat, I commented out the conversion of 'answer' into decimal and it works. (Type is 'Decimal'.) But I swear yesterday that broke the program... I don't even know what's going on anymore.

But omitting "str" from

code:

correct = Decimal(str(round(sqrt(problem), dec_places)))

still breaks it. 'correct' for root of 67 comes out as 8.199999999999999289457264239899814128875732421875.

supermikhail posted:

code:

    @staticmethod
    def check(problem, answer):
        TwoOperandProblem.check(problem, answer)
        dec_places = -Decimal(str(answer)).as_tuple().exponent
        print("decimal places: " + str(dec_places))
        correct = round(Decimal(problem[0]) / problem[1], dec_places)
        print("correct answer: " + str(correct))
        if answer == correct:
            return True
        else:
            return False

supermikhail posted: