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Selecting with complex criteria from pandas.DataFrame
...(df["B"] > 50) & (df["C"] == 900)]
2 5
3 8
Name: A, dtype: int64
but you can get yourself into trouble because of the difference between a view and a copy doing this for write access. You can use .loc instead:
>>> df.loc[(df["B"] > 50) & (df["C"] == 900), "A"]
2 5...
How do I create an empty array/matrix in NumPy?
...p.array(x)
The result will be:
In [34]: x
Out[34]: array([], dtype=float64)
Therefore you can directly initialize an np array as follows:
In [36]: x= np.array([], dtype=np.float64)
I hope this helps.
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Is there any way to specify a suggested filename when using data: URI?
...ownload attribute:
<a download="logo.gif" href="data:image/gif;base64,R0lGODlhAQABAIAAAAAAAP///yH5BAEAAAAALAAAAAABAAEAAAIBRAA7">Download transparent png</a>
Javascript only: you can save any data URI with this code:
function saveAs(uri, filename) {
var link = docume...
Is there a difference between YES/NO,TRUE/FALSE and true/false in objective-c?
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There is no practical difference provided you use BOOL variables as booleans. C processes bool...
Make git automatically remove trailing whitespace before committing
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cmcgintycmcginty
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SQL select only rows with max value on a column [duplicate]
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Yet another solution is to use a correlated subquery:
select yt.id, yt.rev, yt.contents
fr...
ASP MVC in IIS 7 results in: HTTP Error 403.14 - Forbidden
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Don't forget that for a 64 bit system it's "Framework64". I.e., Windows\Microsoft.NET\Framework64\v4.xxx.xxx
– grahamesd
Dec 17 '15 at 21:29
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What is the difference between List (of T) and Collection(of T)?
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In C#, there are three concepts for representing a bag of objects. In order of increasing featu...
How do I typedef a function pointer with the C++11 using syntax?
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Remove all child elements of a DOM node in JavaScript
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Use modern Javascript, with remove!
const parent = document.getElementById("foo")
while (parent...