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Why were pandas merges in python faster than data.table merges in R in 2012?
... coerce character to
factor. Factors are still supported. Implements FR#1493, FR#1224
and (partially) FR#951.
New functions chmatch() and %chin%, faster versions of match()
and %in% for character vectors. R's internal string cache is
utilised (no hash table is built). They are about 4 times faster
t...
XML Document to String
...the simplest way to get the String representation of a XML Document ( org.w3c.dom.Document )? That is all nodes will be on a single line.
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Is there a MySQL option/feature to track history of changes to records?
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Octavian Catusanu
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answered Sep 24 '12 at 11:45
Neville KuytNeville Kuy...
Iterate over object keys in node.js
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edited Feb 17 '15 at 15:34
thepeer
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answered Se...
Convert a character digit to the corresponding integer in C
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153
As per other replies, this is fine:
char c = '5';
int x = c - '0';
Also, for error checking, ...
Undo VS 'Exclude from project'?
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edited Sep 3 '12 at 13:12
Owais Qureshi
3,94255 gold badges3535 silver badges5858 bronze badges
...
Only read selected columns
... header = TRUE)
Year Jan Feb Mar Apr May Jun
1 2009 -41 -27 -25 -31 -31 -39
2 2010 -41 -27 -25 -31 -31 -39
3 2011 -21 -27 -2 -6 -10 -32
Change "integer" to one of the accepted types as detailed in ?read.table depending on the real type of data.
data.txt looks like this:
$ cat data.tx...