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Fast way of counting non-zero bits in positive integer
...nt() took about 1/20th of the time of bin(n).count("1"). So if you can install gmpy, use that.
To answer a question in the comments, for bytes I'd use a lookup table. You can generate it at runtime:
counts = bytes(bin(x).count("1") for x in range(256)) # py2: use bytearray
Or just define it lit...
What's the best way of scraping data from a website? [closed]
...programming interface or another mechanism to access that data programmatically.
2 Answers
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Why is UICollectionViewCell's outlet nil?
...I don't use it, it gives me error Assertion failure in -[UICollectionView _dequeueReusableViewOfKind:withIdentifier:forIndexPath:viewCategory:]
– Shaheera
Jun 30 '16 at 11:04
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Add & delete view from Layout
...ld");
ViewGroup Layout = (LinearLayout) getActivity().findViewById(R.id.my_layout);
layout.addView(view);
There are also a number of remove methods. Check the documentation of ViewGroup.
One simple way to remove view from a layout can be like,
layout.removeAllViews(); // then you will end up h...
Return JSON response from Flask view
...om flask import jsonify
@app.route('/summary')
def summary():
d = make_summary()
return jsonify(d)
As of Flask 0.11, you can pass any JSON-serializable type, not just dict, as the top level object.
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Is it possible to roll back CREATE TABLE and ALTER TABLE statements in major SQL databases?
...cle Database 11g Release 2 and above - by default, no, but an alternative called edition-based redefinition exists
Older versions of Oracle - no; DDL causes an implicit commit
SQL Server - yes
Sybase Adaptive Server - yes
DB2 - yes
Informix - yes
Firebird (Interbase) - yes
SQLite also appears to h...
Single quotes vs. double quotes in C or C++
..., that is sizeof 'a' is 4 in an architecture where ints are 32bit (and CHAR_BIT is 8), while sizeof(char) is 1 everywhere.
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How to disable JavaScript in Chrome Developer Tools?
...sable-javascript doesn't work with google-chrome-stable-51.0.2704.106-1.x86_64.
– Cristian Ciupitu
Jul 16 '16 at 20:44
1
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Changing the maximum length of a varchar column?
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You need
ALTER TABLE YourTable ALTER COLUMN YourColumn <<new_datatype>> [NULL | NOT NULL]
But remember to specify NOT NULL explicitly if desired.
ALTER TABLE YourTable ALTER COLUMN YourColumn VARCHAR (500) NOT NULL;
If you leave it unspecified as below...
ALTER TABLE Your...
How to explain callbacks in plain english? How are they different from calling one function from ano
How to explain callbacks in plain English? How are they different from calling one function from another function taking some context from the calling function? How can their power be explained to a novice programmer?
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