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What is the easiest way to remove the first character from a string?
...t;> "12,23,987,43"
I'm always looking for the fastest and most readable way of doing things:
require 'benchmark'
N = 1_000_000
puts RUBY_VERSION
STR = "[12,23,987,43"
Benchmark.bm(7) do |b|
b.report('[0]') { N.times { "[12,23,987,43"[0] = '' } }
b.report('sub') { N.times { "[12,23,98...
How do I merge changes to a single file, rather than merging commits?
I have two branches (A and B) and I want to merge a single file from branch A with a corresponding single file from Branch B.
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Access object child properties using a dot notation string [duplicate]
I'm temporarily stuck with what appears to be a very simple JavaScript problem, but maybe I'm just missing the right search keywords!
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Logical operators for boolean indexing in Pandas
I'm working with boolean index in Pandas.
The question is why the statement:
3 Answers
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Renaming columns in pandas
I have a DataFrame using pandas and column labels that I need to edit to replace the original column labels.
27 Answers
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Overloading Macro on Number of Arguments
...e these macros:
FOO(World, !) # expands to FOO2(World, !)
FOO(foo,bar,baz) # expands to FOO3(foo,bar,baz)
If you want a fourth one:
#define GET_MACRO(_1,_2,_3,_4,NAME,...) NAME
#define FOO(...) GET_MACRO(__VA_ARGS__, FOO4, FOO3, FOO2)(__VA_ARGS__)
FOO(a,b,c,d) # expeands t...
Can virtual functions have default parameters?
If I declare a base class (or interface class) and specify a default value for one or more of its parameters, do the derived classes have to specify the same defaults and if not, which defaults will manifest in the derived classes?
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Remove duplicated rows
...frame to the columns you need, then use the unique function :D
# in the above example, you only need the first three columns
deduped.data <- unique( yourdata[ , 1:3 ] )
# the fourth column no longer 'distinguishes' them,
# so they're duplicates and thrown out.
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MySQL - Rows to Columns
I tried to search posts, but I only found solutions for SQL Server/Access. I need a solution in MySQL (5.X).
12 Answers
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In pure functional languages, is there an algorithm to get the inverse function?
... is there an algorithm to get the inverse of a function, (edit) when it is bijective? And is there a specific way to program your function so it is?
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