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Check if a given key already exists in a dictionary
...()
for i in range(100):
key = i % 10
d[key] = d.get(key, 0) + 1
and if you wanted to always ensure a default value for any key you can either use dict.setdefault() repeatedly or defaultdict from the collections module, like so:
from collections import defaultdict
d = defaultdict(int)
f...
Why can't I use float value as a template parameter?
...
The current C++ standard does not allow float (i.e. real number) or character string literals to be used as template non-type parameters. You can of course use the float and char * types as normal arguments.
Perhaps the author is using a com...
Assign pandas dataframe column dtypes
...you have to use the explicit conversions:
pd.to_datetime, pd.to_timedelta and pd.to_numeric
(As mentioned below, no more "magic", convert_objects has been deprecated in 0.17)
df = pd.DataFrame({'x': {0: 'a', 1: 'b'}, 'y': {0: '1', 1: '2'}, 'z': {0: '2018-05-01', 1: '2018-05-02'}})
df.dtypes
x ...
How to duplicate a git repository? (without forking)
I have two repositories, and I need to copy whole of one onto the other empty one which has different access levels from the first one. The copy and the mother repository should not be linked together.
...
What does “pending” mean for request in Chrome Developer Window?
...enaming the file so that it doesn't contain "ad" in the URL also fixes it, and is obviously a better solution. Unless it's an advertisement, in which case you should leave it like that. :)
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JSF backing bean structure (best practices)
...et people's opinions on best practices for the interface between JSF pages and backing beans.
6 Answers
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Initialize a byte array to a certain value, other than the default null? [duplicate]
... { 0x20, 0x20, 0x20, 0x20, 0x20, 0x20, 0x20 };
For larger arrays use a standard for loop. This is the most readable and efficient way to do it:
var sevenThousandItems = new byte[7000];
for (int i = 0; i < sevenThousandItems.Length; i++)
{
sevenThousandItems[i] = 0x20;
}
Of course, if you...
When do I need to use Begin / End Blocks and the Go keyword in SQL Server?
Can someone tell me when and where I need to use begin and end blocks in SQL Server?
Also, what exactly does the Go keyword do?
...
Is XSLT worth it? [closed]
...formed into HTML via XSLT. I played around (struggled) with it for a while and got it to a very basic level but then was too annoyed by the limitations I was encountering (which may well have been limitations of my knowledge) and when I read a blog suggesting to ditch XSLT and just write your own XM...
Benefits of prototypal inheritance over classical?
So I finally stopped dragging my feet all these years and decided to learn JavaScript "properly". One of the most head-scratching elements of the languages design is it's implementation of inheritance. Having experience in Ruby, I was really happy to see closures and dynamic typing; but for the li...