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Bundler: Command not found
I am hosting on a vps, ubuntu 10.04, rails 3, ruby and mysql installed correctly by following some tutorials. If I run bundle check or bundle install I get the error '-bash: bundle: command not found'. From gem list --local I see 'bundler (1.0.2, 1.0.0)' is installed.
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How do you know when to use fold-left and when to use fold-right?
... you use a left fold. Example (haskell-style pseudocode)
foldl (-) [1, 2, 3] == (1 - 2) - 3 == 1 - 2 - 3 // - is left-associative
If your operator is right-associative (right fold), the parentheses would be set like this:
A x (B x (C x D))
Example: Cons-Operator
foldr (:) [] [1, 2, 3] == 1 : ...
How to download Xcode DMG or XIP file?
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4943
You can find the DMGs or XIPs for Xcode and other development tools on https://developer.apple.c...
HSL to RGB color conversion
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308
Garry Tan posted a Javascript solution on his blog (which he attributes to a now defunct mjija...
How to remove element from an array in JavaScript?
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355
For a more flexible solution, use the splice() function. It allows you to remove any item in ...
how do I insert a column at a specific column index in pandas?
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388
see docs: http://pandas.pydata.org/pandas-docs/stable/generated/pandas.DataFrame.insert.html
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How do I forward parameters to other command in bash script?
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3 Answers
3
Active
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Dynamically select data frame columns using $ and a character value
... a reproducible example below:
# set seed for reproducibility
set.seed(123)
df <- data.frame( col1 = sample(5,10,repl=T) , col2 = sample(5,10,repl=T) , col3 = sample(5,10,repl=T) )
# We want to sort by 'col3' then by 'col1'
sort_list <- c("col3","col1")
# Use 'do.call' to call order. Sec...
C++ preprocessor __VA_ARGS__ number of arguments
....) \
PP_ARG_N(__VA_ARGS__)
#define PP_ARG_N( \
_1, _2, _3, _4, _5, _6, _7, _8, _9,_10, \
_11,_12,_13,_14,_15,_16,_17,_18,_19,_20, \
_21,_22,_23,_24,_25,_26,_27,_28,_29,_30, \
_31,_32,_33,_34,_35,_36,_37,_38,_39,_40, \
_41,_42,_43,_44,_45,_46,_47...
Does the ternary operator exist in R?
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306
As if is function in R and returns the latest evaluation, if-else is equivalent to ?:.
> a...