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Should I use a data.frame or a matrix?
...mine the choice.
Also:
Matrices are more memory efficient:
m = matrix(1:4, 2, 2)
d = as.data.frame(m)
object.size(m)
# 216 bytes
object.size(d)
# 792 bytes
Matrices are a necessity if you plan to do any linear algebra-type of operations.
Data frames are more convenient if you frequently refer ...
How do I find out if first character of a string is a number?
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edited Oct 2 '12 at 14:13
answered Aug 3 '09 at 15:43
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Git: Merge a Remote branch locally
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answered Feb 9 '14 at 0:23
VonCVonC
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Where is the “Fold” LINQ Extension Method?
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JasonJason
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SQLite - increase value by a certain number
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edited Apr 13 '09 at 15:44
answered Apr 13 '09 at 15:39
K...
How to get the seconds since epoch from the time + date output of gmtime()?
...time.strptime('Jul 9, 2009 @ 20:02:58 UTC', '%b %d, %Y @ %H:%M:%S UTC'))
1247169778
More information about calendar module here
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creating list of objects in Javascript
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var list = [
{ date: '12/1/2011', reading: 3, id: 20055 },
{ date: '13/1/2011', reading...
django 1.5 - How to use variables inside static tag
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edited Apr 26 '14 at 20:16
Barney Szabolcs
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Django import error - no module named django.conf.urls.defaults
...ite. The issue has been fixed in graphite's master branch and version 0.9.14+.
In Django 1.8+ you can remove patterns from the import, and use a list of url()s instead.
from django.conf.urls import url, include
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delete map[key] in go?
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edited Jul 21 '15 at 6:34
coolaj86
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