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Referring to the null object in Python
...
SyntaxError: cannot assign to keyword
It's therefore safe to assume that all None references are the same. There isn't any "custom" None.
To test for None use the is operator
When writing code you might be tempted to test for Noneness like this:
if value==None:
pass
Or to test for falsehood l...
How to copy data from one table to another new table in MySQL?
...d,from_uid,now(),'Pending','Assigned'
FROM table1
If you want to include all rows from table1. Otherwise you can add a WHERE statement to the end if you want to add only a subset of table1.
I hope this helps.
share
...
What is the difference between '@' and '=' in directive scope in AngularJS?
...ot create a new scope. It will use the parent scope. You can then access all of the parent scope properties directly.
The documentation says "Often it's desirable to pass data from the isolated scope via an expression and to the parent scope", but that seems to work fine with bidirectional bin...
Pass a parameter to a fixture function
... through the tester fixture.
I had a similar problem--I have a fixture called test_package, and I later wanted to be able to pass an optional argument to that fixture when running it in specific tests. For example:
@pytest.fixture()
def test_package(request, version='1.0'):
...
request....
Input and output numpy arrays to h5py
I have a Python code whose output is a sized matrix, whose entries are all of the type float . If I save it with the extension .dat the file size is of the order of 500 MB. I read that using h5py reduces the file size considerably. So, let's say I have the 2D numpy array named A . How do I ...
Unknown column in 'field list' error on MySQL Update query
...Thank you. I was trying to figure out why my query in PHP was not working, all I had to do was add the single quotes.
– RiCHiE
Jul 2 '16 at 5:12
1
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Get value from SimpleXMLElement Object
... i can't believe this is so complicated. why would they make a class called "getName" but not "getValue"? why would they print empty string if you printed it instead of converted it manually to (string). WHY??
– user151496
Oct 17 '16 at 12:31
...
What's the best practice for primary keys in tables?
...
I follow a few rules:
Primary keys should be as small as necessary. Prefer a numeric type because numeric types are stored in a much more compact format than character formats. This is because most primary keys will be foreign keys in another table as well as used in multipl...
Creating a config file in PHP
...ne simple but elegant way is to create a config.php file (or whatever you call it) that just returns an array:
<?php
return array(
'host' => 'localhost',
'username' => 'root',
);
And then:
$configs = include('config.php');
...
Is the list of Python reserved words and builtins available in a library?
...break', 'class', 'continue', 'def',
'del', 'elif', 'else', 'except', 'finally', 'for', 'from', 'global', 'if', 'import',
'in', 'is', 'lambda', 'nonlocal', 'not', 'or', 'pass', 'raise', 'return', 'try',
'while', 'with', 'yield']
If you want to include built-in names as well (Python 3), then c...