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In Python how should I test if a variable is None, True or False
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a = 'foo' if a: print 'its true' a is not actually TRUE, it's just not none
– wesm
Apr 3 '15 at 21:06
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How to pass arguments into a Rake task with environment in Rails? [duplicate]
...e." (I mention this only for future browsers, since it suggests that eventually :needs won't be supported any longer. The section is called "Deprecated Task Paramaters Format"...)
– Telemachus
Sep 1 '09 at 23:42
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How do I center floated elements?
...ine-block works cross-browser, even on IE6 as long as the element is originally an inline element.
Quote from quirksmode:
An inline block is placed inline (ie. on the same line as adjacent content), but it behaves as a block.
this often can effectively replace floats:
The real use of th...
Is there a way to change context to iframe in javascript console?
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Chrome 15 allows you to change the scope of the console. On the bottom of the console, next to the clear console button, there is a menu that says <top frame> which will give a list of available frames:
Firefox has a similar ...
pandas GroupBy columns with NaN (missing) values
...n the Missing Data section of the docs:
NA groups in GroupBy are automatically excluded. This behavior is consistent with R, for example.
One workaround is to use a placeholder before doing the groupby (e.g. -1):
In [11]: df.fillna(-1)
Out[11]:
a b
0 1 4
1 2 -1
2 3 6
In [12]: df.fil...
How to format a JavaScript date
...t (which is part of the
ECMAScript Internationalization API), and then manually create a string
with the delimiters you want.
To do this, you can use DateTimeFormat#formatToParts. You could
destructure the array, but that is not ideal, as the array output depends on the
locale:
// example 1
cons...
JNI converting jstring to char *
...ctions.html
concerning your problem you can use this
JNIEXPORT void JNICALL Java_ClassName_MethodName(JNIEnv *env, jobject obj, jstring javaString)
{
const char *nativeString = env->GetStringUTFChars(javaString, 0);
// use your string
env->ReleaseStringUTFChars(javaString, nat...
Python nested functions variable scoping [duplicate]
I've read almost all the other questions about the topic, but my code still doesn't work.
10 Answers
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How to automate createsuperuser on django?
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Personally I don't think deleting the user on each build is a good idea. You risk unintentionally deleting any associated records via a cascade delete. A safer option is to simply bail-out if the user already exists (or update the ...
Initialize a long in Java
...need to append "L" to the end.
It can be either uppercase or lowercase.
All the numeric values are by default int. Even when you do any operation of byte with any integer, byte is first promoted to int and then any operations are performed.
Try this
byte a = 1; // declare a byte
a = a*2; // y...