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Python Regex - How to Get Positions and Values of Matches
How can I get the start and end positions of all matches using the re module? For example given the pattern r'[a-z]' and the string 'a1b2c3d4' I'd want to get the positions where it finds each letter. Ideally, I'd like to get the text of the match back too.
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in iPhone App How to detect the screen resolution of the device
...ays this will return a 1.0f, while Retina Display devices will give a 2.0f and the iPhone 6 Plus (Retina HD) will give a 3.0f.
Now if you want to get the pixel width & height of the iOS device screen you just need to do one simple thing.
CGSize screenSize = CGSizeMake(screenBounds.size.width *...
C++ Double Address Operator? (&&)
I'm reading STL source code and I have no idea what && address operator is supposed to do. Here is a code example from stl_vector.h :
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Sort points in clockwise order?
...e other.
Using it you can construct a less-than relation to compare points and determine the order in which they should appear in the sorted array. But you have to define where is the beginning of that order, I mean what angle will be the starting one (e.g. the positive half of x-axis).
The code fo...
How do I retrieve the number of columns in a Pandas data frame?
How do you programmatically retrieve the number of columns in a pandas dataframe? I was hoping for something like:
6 Answer...
SQLite INSERT - ON DUPLICATE KEY UPDATE (UPSERT)
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@Smith I meant using plain UPDATE and INSERT statements and checking return value.
– codeholic
Nov 17 '13 at 14:47
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How to find current transaction level?
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just run DBCC useroptions and you'll get something like this:
Set Option Value
--------------------------- --------------
textsize 2147483647
language us_english
dateformat mdy
d...
error: ‘NULL’ was not declared in this scope
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NULL is not a keyword. It's an identifier defined in some standard headers. You can include
#include <cstddef>
To have it in scope, including some other basics, like std::size_t.
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Flask-SQLAlchemy import/context issue
...y
db = SQLAlchemy()
class Member(db.Model):
# fields here
pass
And then in your application setup you can call init_app:
# apps.application.py
from flask import Flask
from apps.members.models import db
app = Flask(__name__)
# later on
db.init_app(app)
This way you can avoid cyclical ...
How do I find out if first character of a string is a number?
...s, you must first be sure that the string isn't empty. If it is, charAt(0) and substring(0, 1) will throw a StringIndexOutOfBoundsException. startsWith does not have this problem.
To make the entire condition one line and avoid length checks, you can alter the regexes to the following:
s.matches("...