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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 you create nested dict in Python?
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ab load testing
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edited Nov 11 '14 at 15:38
wpp
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javascript remove “disabled” attribute from html input
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answered Mar 31 '15 at 13:40
Dragos RusuDragos Rusu
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How do I calculate the normal vector of a line segment?
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How to redirect stderr to null in cmd.exe
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atzzatzz
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Adding 'serial' to existing column in Postgres
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134
Look at the following commands (especially the commented block).
DROP TABLE foo;
DROP TABLE bar...
Bare asterisk in function arguments?
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KimvaisKimvais
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Unpacking, extended unpacking and nested extended unpacking
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Since the OP gave a long list examples, it's only fitting that you give a long list of explanations.
– John Y
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