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Change column type from string to float in Pandas
...ost) any other type (even if it's not necessarily sensible to do so). Also allows you to convert to categorial types (very useful).
infer_objects() - a utility method to convert object columns holding Python objects to a pandas type if possible.
convert_dtypes() - convert DataFrame columns to the ...
How to know if two arrays have the same values
..., i.e. ['a', 'b'] and ['a,b']. I would only recommend this technique for small throwaway scripts.
– alex
Mar 7 '16 at 16:23
1
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Proper use of beginBackgroundTaskWithExpirationHandler
...l need to wrap it in a background task. It's also very important that you call endBackgroundTask when you're finished - otherwise the app will be killed after its allotted time has expired.
Mine tend look something like this:
- (void) doUpdate
{
dispatch_async(dispatch_get_global_queue(DISPAT...
Multiple Inheritance in PHP
...tMessage class, and sending algorithm is delegated to dispatcher. This is called Strategy Pattern, you can read more on it here.
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Numpy - add row to array
...2, 0]])
X = array([[0, 1, 2], [1, 2, 0], [2, 1, 2], [3, 2, 0]])
add to A all rows from X where the first element < 3:
import numpy as np
A = np.vstack((A, X[X[:,0] < 3]))
# returns:
array([[0, 1, 2],
[0, 2, 0],
[0, 1, 2],
[1, 2, 0],
[2, 1, 2]])
...
A semantics for Bash scripts?
...patchwork together little scripts that appear to work. However, I don't really know what's going on, and I was hoping for a more formal introduction to Bash as a programming language. For example: What is the evaluation order? what are the scoping rules? What is the typing discipline, e.g. is ever...
Can a C# lambda expression have more than one statement?
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(I'm assuming you're really talking about multiple statements rather than multiple lines.)
You can use multiple statements in a lambda expression using braces, but only the syntax which doesn't use braces can be converted into an expression tree:
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How can I change an element's class with JavaScript?
...r, going into detail on this is beyond the scope of the answer.
To change all classes for an element:
To replace all existing classes with one or more new classes, set the className attribute:
document.getElementById("MyElement").className = "MyClass";
(You can use a space-delimited list to app...
Run php script as daemon process
...tions need to be taken as soon as instruction arrives. I know PHP is not really the best option for daemon processes due to memory management issues, but due to various reasons I have to use PHP in this case. I came across a tool by libslack called Daemon ( http://libslack.org/daemon ) it seems to h...
float:left; vs display:inline; vs display:inline-block; vs display:table-cell;
... that now though. But the important thing is it does work, and it works in all browsers (even IE6/7), so use it if you like it.
The additional markup for clearing may not be necessary if you use the :after selector to clear the floats, but this isn't an option if you want to support IE6 or IE7.
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