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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...
Calling closure assigned to object property directly
...sn't work on a StdClass.
Before PHP7, you'd have to implement the magic __call method to intercept the call and invoke the callback (which is not possible for StdClass of course, because you cannot add the __call method)
class Foo
{
public function __call($method, $args)
{
if(is_...
how to return index of a sorted list? [duplicate]
...ray([2,3,1,4,5])
>>> vals
array([2, 3, 1, 4, 5])
>>> sort_index = numpy.argsort(vals)
>>> sort_index
array([2, 0, 1, 3, 4])
If not available, taken from this question, this is the fastest method:
>>> vals = [2,3,1,4,5]
>>> sorted(range(len(vals)), key=...
Convert an image (selected by path) to base64 string
...e to retrieve the base64 string
public static string ImageToBase64(string _imagePath)
{
string _base64String = null;
using (System.Drawing.Image _image = System.Drawing.Image.FromFile(_imagePath))
{
using (MemoryStream _mStream = new MemoryStream())
...
Is APC compatible with PHP 5.4 or PHP 5.5?
...hp 5.4 release (I wish they would have included APC in PHP core like originally planned).
14 Answers
...
Why do we need fibers
...Ruby class in Ruby 1.9. These are incredibly useful.
In Ruby 1.9, if you call almost any iterator method on the core classes, without passing a block, it will return an Enumerator.
irb(main):001:0> [1,2,3].reverse_each
=> #<Enumerator: [1, 2, 3]:reverse_each>
irb(main):002:0> "abc"....
ConnectionTimeout versus SocketTimeout
...A connection timeout occurs only upon starting the TCP connection. This usually happens if the remote machine does not answer. This means that the server has been shut down, you used the wrong IP/DNS name, wrong port or the network connection to the server is down.
A socket timeout is dedicated to ...
addEventListener not working in IE8
...
Try:
if (_checkbox.addEventListener) {
_checkbox.addEventListener("click", setCheckedValues, false);
}
else {
_checkbox.attachEvent("onclick", setCheckedValues);
}
Update::
For Internet Explorer versions prior to IE9, attach...
lenses, fclabels, data-accessor - which library for structure access and mutation is better
...f these libraries also provide a bunch of extra combinators on top, and usually some form of template haskell machinery to automatically generate lenses for the fields of simple record types.
With that in mind, we can turn to the different implementations:
Implementations
fclabels
fclabels is pe...
partial string formatting
...he advanced string formatting methods, similar to the string template safe_substitute() function?
21 Answers
...