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How do I detect unsigned integer multiply overflow?
I was writing a program in C++ to find all solutions of a b = c , where a , b and c together use all the digits 0-9 exactly once. The program looped over values of a and b , and it ran a digit-counting routine each time on a , b and ab to check if the digits condition was satisfied.
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Find current directory and file's directory [duplicate]
...tive to the current working directory and is not changed by an os.chdir() call.)
To get the current working directory use
import os
cwd = os.getcwd()
Documentation references for the modules, constants and functions used above:
The os and os.path modules.
The __file__ constant
os.path.rea...
How to set or change the default Java (JDK) version on OS X?
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those really are backticks the export line
– David West
Nov 27 '14 at 19:38
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Why doesn't Python have a sign function?
... it wasn't accepted, because they didn't agree on what it should return in all the edge cases (+/-0, +/-nan, etc)
So they decided to implement only copysign, which (although more verbose) can be used to delegate to the end user the desired behavior for edge cases - which sometimes might require the...
Passing parameters to JavaScript files
...it or define a new object. The intent is to create a global namespace, normally I will use sub namespaces so this line helps to avoid re-defining the top level namespace. 2) Yes, it has created a singleton.
– Naeem Sarfraz
Apr 7 '15 at 9:41
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How can I use UUIDs in SQLAlchemy?
... dialect supports UUID columns. This is easy (and the question is specifically postgres) -- I don't understand why the other answers are all so complicated.
Here is an example:
from sqlalchemy.dialects.postgresql import UUID
from flask_sqlalchemy import SQLAlchemy
import uuid
db = SQLAlchemy()
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Add a new column to existing table in a migration
... });
}
Then you can run your migrations:
php artisan migrate
This is all well covered in the documentation for both Laravel 3:
Schema Builder
Migrations
And for Laravel 4 / Laravel 5:
Schema Builder
Migrations
Edit:
use $table->integer('paid')->after('whichever_column'); to add ...
Importing a CSV file into a sqlite3 database table using Python
...lumn headers in the csv file. And close the connection to the database by calling con.close() at the end.
– Jonas
Aug 8 '16 at 21:31
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How can I find script's directory with Python? [duplicate]
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You need to call os.path.realpath on __file__, so that when __file__ is a filename without the path you still get the dir path:
import os
print(os.path.dirname(os.path.realpath(__file__)))
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Get names of all keys in the collection
I'd like to get the names of all the keys in a MongoDB collection.
21 Answers
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