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Should I use a data.frame or a matrix?
...e 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 to ...
Passing parameters in rails redirect_to
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edited Oct 21 '15 at 14:19
bmalets
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How to delete an element from an array in C#
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342
If you want to remove all instances of 4 without needing to know the index:
LINQ: (.NET Framewo...
PostgreSQL - max number of parameters in “IN” clause?
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Jordan S. JonesJordan S. Jones
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add a ...
How to insert a character in a string at a certain position?
...igit value. I want to display it as a String with a decimal point (.) at 2 digits from the end of int . I wanted to use a float but was suggested to use String for a better display output (instead of 1234.5 will be 1234.50 ). Therefore, I need a function that will take an int as paramete...
Checking if a string can be converted to float in Python
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edited Nov 11 '19 at 12:29
Richard Simões
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a...
How to calculate “time ago” in Java?
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edited Nov 28 '16 at 8:15
jdersen
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answered Oct 4 '10...
Validate phone number with JavaScript
...ectly. It validates that the phone number is in one of these formats:
(123) 456-7890 or 123-456-7890
26 Answers
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Ruby: What is the easiest way to remove the first element from an array?
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291
"pop"ing the first element of an Array is called "shift" ("unshift"
being the operation of add...