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How do I create an empty array/matrix in NumPy?
...t I would normally use a list. I want to create an empty array (or matrix) and then add one column (or row) to it at a time.
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Python != operation vs “is not”
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== is an equality test. It checks whether the right hand side and the left hand side are equal objects (according to their __eq__ or __cmp__ methods.)
is is an identity test. It checks whether the right hand side and the left hand side are the very same object. No methodcalls ...
INNER JOIN ON vs WHERE clause
... easier to see this with the WHERE syntax.
As for your example, in MySQL (and in SQL generally) these two queries are synonyms.
Also note that MySQL also has a STRAIGHT_JOIN clause.
Using this clause, you can control the JOIN order: which table is scanned in the outer loop and which one is in the...
angular.service vs angular.factory
I have seen both angular.factory() and angular.service() used to declare services; however, I cannot find angular.service anywhere in official documentation.
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How to connect to Mysql Server inside VirtualBox Vagrant?
I mounted a new VirtualBox Machine with Vagrant, and inside that VM I installed Mysql Server. How can I connect to that server outside the vm? I already forward the port 3306 of the Vagrantfile , but when I try to connect to the mysql server, it`s resposts with the error:
'reading initial communica...
Resize image to full width and fixed height with Picasso
... using Picasso. I need to rise the image's width to the full device width, and to display the center part of the image cropped by a fixed height (150dp). I currently have the following code:
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Should I learn C before learning C++? [closed]
I visited a university CS department open day today and in the labs tour we sat down to play with a couple of final-year projects from undergraduate students. One was particularly good - a sort of FPS asteroids game. I decided to take a peek in the src directory to find it was done in C++ (most of...
How to get controls in WPF to fill available space?
...eriving from Panel implements distinct layout logic performed in Measure() and Arrange():
Measure() determines the size of the panel and each of its children
Arrange() determines the rectangle where each control renders
The last child of the DockPanel fills the remaining space. You can disable ...
Programmatically open new pages on Tabs
... Firefox tip, now I have updated my TargetKiller addon to remove "_newtab" and "newtab". :P
– thenonhacker
Jan 9 '09 at 9:38
1
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Can't pickle when using multiprocessing Pool.map()
... is that multiprocessing must pickle things to sling them among processes, and bound methods are not picklable. The workaround (whether you consider it "easy" or not;-) is to add the infrastructure to your program to allow such methods to be pickled, registering it with the copy_reg standard librar...