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Reshaping data.frame from wide to long format
...s melt/cast. Here is a solution with reshape, assuming your data frame is called d:
reshape(d,
direction = "long",
varying = list(names(d)[3:7]),
v.names = "Value",
idvar = c("Code", "Country"),
timevar = "Year",
times = 1950:1954)
...
Streaming a video file to an html5 video player with Node.js so that the video controls continue to
...to get the size of the file without reading the whole file into memory. Finally, use fs.createReadStream to send the requested part to the client.
var fs = require("fs"),
http = require("http"),
url = require("url"),
path = require("path");
http.createServer(function (req, res) {
if ...
How to grep (search) committed code in the Git history
...s and the like), you need to do:
git grep <regexp> $(git rev-list --all)
git rev-list --all | xargs git grep <expression> will work if you run into an "Argument list too long" error.
If you want to limit the search to some subtree (for instance, "lib/util"), you will need to pass tha...
Which Boost features overlap with C++11?
...)
Local function → Lambda expression
Min-Max → std::minmax, std::minmax_element
Ratio → std::ratio
Static Assert → static_assert
Thread → <thread>, etc (but check this question).
Typeof → auto, decltype
Value initialized → List-initialization (§8.5.4/3)
Math/Special Functions ...
YYYY-MM-DD format date in shell script
...
$(date +%F_%H-%M-%S)
can be used to remove colons (:) in between
output
2018-06-20_09-55-58
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String difference in Bash
...e is some difference between the two strings?
– alpha_989
Aug 10 '17 at 15:28
@alpha_989 , here's your answer: $ diff ...
Search for one value in any column of any table inside a database
...
How to search all columns of all
tables in a database for a keyword?
http://vyaskn.tripod.com/search_all_columns_in_all_tables.htm
EDIT: Here's the actual T-SQL, in case of link rot:
CREATE PROC SearchAllTables
(
@SearchStr nvarchar...
Getting the name of the currently executing method
...
Thread.currentThread().getStackTrace() will usually contain the method you’re calling it from but there are pitfalls (see Javadoc):
Some virtual machines may, under some circumstances, omit one or more stack frames from the stack trace. In the extreme case, a virtua...
Inspect attached event handlers for any DOM element
...k= handler or HTML <element onclick="handler"> can be retrieved trivially from the element.onclick property from script or in-debugger.
Event handlers attached using DOM Level 2 Events addEventListener methods and IE's attachEvent cannot currently be retrieved from script at all. DOM Level 3 ...
What is in your .vimrc? [closed]
Vi and Vim allow for really awesome customization, typically stored inside a .vimrc file. Typical features for a programmer would be syntax highlighting, smart indenting and so on.
...