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Can't install Ruby under Lion with RVM – GCC issues
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16 Answers
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Mean per group in a data.frame [duplicate]
...aggregate was designed for:
d <- read.table(text=
'Name Month Rate1 Rate2
Aira 1 12 23
Aira 2 18 73
Aira 3 19 45
Ben 1 53 19
Ben 2 22 87
Ben 3 19 45
Cat 1 22 ...
In Matlab, when is it optimal to use bsxfun?
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152
+500
There ...
how to change default python version?
...onfusing that when I type python -V in Terminal it says that Python 2.6.1 , how can I change the default python version?
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Python Dictionary Comprehension
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>>> d = {n: n**2 for n in range(5)}
>>> print d
{0: 0, 1: 1, 2: 4, 3: 9, 4: 16}
If you want to set them all to True:
>>> d = {n: True for n in range(5)}
>>> print d
{0: True, 1: True, 2: True, 3: True, 4: True}
What you seem to be asking for is a way to set...
Bubble Sort Homework
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127
To explain why your script isn't working right now, I'll rename the variable unsorted to sorte...
What does it mean by select 1 from table?
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15 Answers
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Ruby: What is the easiest way to remove the first element from an array?
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11 Answers
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How to write a bash script that takes optional input arguments?
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You could use the default-value syntax:
somecommand ${1:-foo}
The above will, as described in Bash Reference Manual - 3.5.3 Shell Parameter Expansion [emphasis mine]:
If parameter is unset or null, the expansion of word is substituted. Otherwise, the value of parameter is ...