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Example of Named Pipes
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174
using System;
using System.IO;
using System.IO.Pipes;
using System.Linq;
using System.Text;
us...
Summarizing multiple columns with dplyr? [duplicate]
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#> <int> <dbl> <dbl> <dbl> <dbl>
#> 1 1 3.08 2.98 2.98 2.91
#> 2 2 3.03 3.04 2.97 2.87
#> 3 3 2.85 2.95 2.95 3.06
If you want to summarize only certain columns, use summarise_at or summarise_if functions.
Alternatively, the purrrl...
Debug a java application without starting the JVM with debug arguments
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edited Jan 6 '14 at 12:58
Zitrax
14.9k1313 gold badges7777 silver badges9393 bronze badges
a...
How do I use define_method to create class methods?
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196
I think in Ruby 1.9 you can do this:
class A
define_singleton_method :loudly do |message|
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Check if a table exists in Rails
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edited Mar 29 '17 at 2:24
answered Jul 5 '11 at 23:49
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Difference between len() and .__len__()?
Is there any difference between calling len([1,2,3]) or [1,2,3].__len__() ?
4 Answers
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“Width equals height” constraint in Interface Builder
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187
Update Xcode 5.1b5
Ctrl+click and drag from a view and release while the pointer is over th...
Argparse: Required argument 'y' if 'x' is present
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124
No, there isn't any option in argparse to make mutually inclusive sets of options.
The simple...
How to read the output from git diff?
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Lets take a look at example advanced diff from git history (in commit 1088261f in git.git repository):
diff --git a/builtin-http-fetch.c b/http-fetch.c
similarity index 95%
rename from builtin-http-fetch.c
rename to http-fetch.c
index f3e63d7..e8f44ba 100644
--- a/builtin-http-fetch.c
+++ b/ht...