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Rename Pandas DataFrame Index
...er:
df.rename_axis('names').rename_axis('attributes', axis='columns')
If you set the index with some of the columns, then the column name will become the new index level name. Let's append to index levels to our original DataFrame:
df1 = df.set_index(['state', 'color'], append=True)
df1
No...
How to insert an item at the beginning of an array in PHP?
...
Use array_unshift($array, $item);
$arr = array('item2', 'item3', 'item4');
array_unshift($arr , 'item1');
print_r($arr);
will give you
Array
(
[0] => item1
[1] => item2
[2] => item3
[3] => item4
)
...
Substitute multiple whitespace with single whitespace in Python [duplicate]
...
A simple possibility (if you'd rather avoid REs) is
' '.join(mystring.split())
The split and join perform the task you're explicitly asking about -- plus, they also do the extra one that you don't talk about but is seen in your example, removin...
Serializing an object to JSON
...
You're looking for JSON.stringify().
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How to repeat a string a variable number of times in C++?
...s in C++ equivalent to the * operator in Python or the x operator in Perl. If you're repeating a single character, the two-argument constructor (as suggested by previous answers) works well:
std::string(5, '.')
This is a contrived example of how you might use an ostringstream to repeat a string n...
How to turn on WCF tracing?
...e "C:\Program Files\Microsoft SDKs\Windows\v7.0A\bin\SvcTraceViewer.exe".
If "SvcTraceViewer.exe" is not on your system, you can download it from the "Microsoft Windows SDK for Windows 7 and .NET Framework 4" package here:
Windows SDK Download
You don't have to install the entire thing, just the...
Create SQL script that create database and tables
...an configure to customise the output, but most of it is self explanatory.
If you are happy with the default options, you can do the whole job in a matter of seconds.
If you want to recreate the data in the database (as a series of INSERTS) I'd also recommend SSMS Tools Pack (Free for SQL 2008 vers...
Is there any pythonic way to combine two dicts (adding values for keys that appear in both)?
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I like that approach! If someone likes keep things close to processing dictionaries, one could also use update() instead of +=: for c in counters[1:]: res.update(c).
– Dr. Jan-Philip Gehrcke
Jan 22 '15 at 21:...
MySQL stored procedure vs function, which would I use when?
I'm looking at MySQL stored procedures and function. What is the real difference?
5 Answers
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How do you match only valid roman numerals with a regular expression?
...|D?C{0,3})(XC|XL|L?X{0,3})(IX|IV|V?I{0,3})$
Breaking it down, M{0,4} specifies the thousands section and basically restrains it to between 0 and 4000. It's a relatively simple:
0: <empty> matched by M{0}
1000: M matched by M{1}
2000: MM matched by M{2}
3000: MMM matche...