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Pandas every nth row
...simpler solution to the accepted answer that involves directly invoking df.__getitem__.
df = pd.DataFrame('x', index=range(5), columns=list('abc'))
df
a b c
0 x x x
1 x x x
2 x x x
3 x x x
4 x x x
For example, to get every 2 rows, you can do
df[::2]
a b c
0 x x x
...
Escape angle brackets in a Windows command prompt
... containing angle brackets (< and >) to a file on a Windows machine. Basically what I want to do is the following:
echo some string < with angle > brackets >>myfile.txt
...
Is there a simple way to remove unused dependencies from a maven pom.xml?
... be carefull while using dependency:analyze, even i was using 'ejp api3'depedency but the report shown it was 'unused and declared'
– Akhil S Kamath
Jul 11 '18 at 10:29
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Rails auto-assigning id that already exists
... answered Feb 27 '13 at 9:40
ApieApie
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When to use Hadoop, HBase, Hive and Pig?
... too huge.
Coming back to the first part of your question, Hadoop is basically 2 things: a Distributed FileSystem (HDFS) + a Computation or Processing framework (MapReduce). Like all other FS, HDFS also provides us storage, but in a fault tolerant manner with high throughput and lower risk of data ...
How do I force Postgres to use a particular index?
...of why and what you can do instead can be found here. The reasons are basically that it's a performance hack that tends to cause more problems later down the line as your data changes, whereas PostgreSQL's optimizer can re-evaluate the plan based on the statistics. In other words, what might be a go...
C++ templates that accept only certain types
...ply forward-declare a global template, but only define (explicitly or partially specialise) it for the valid types:
template<typename T> class my_template; // Declare, but don't define
// int is a valid type
template<> class my_template<int> {
...
};
// All pointer types...
Where can I find my .emacs file for Emacs running on Windows?
I tried looking for the .emacs file for my Windows installation for Emacs, but I could not find it. Does it have the same filename under Windows as in Unix?
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How to convert a List into a comma separated string without iterating List explicitly [dupli
... list of elements.
http://commons.apache.org/proper/commons-lang/javadocs/api-3.3.2/org/apache/commons/lang3/StringUtils.html
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When to use IMG vs. CSS background-image?
...ng icon. This ensures that the meaning of the image can be communicated in all user-agents, including screen readers.
Pragmatic uses of IMG
Use IMG plus alt attribute if the image
is part of the content such as a logo or diagram or person (real person, not stock photo people).
—sanchothefat...