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Group by multiple columns in dplyr, using string vector input
...cumentation here). This lets you use the same functions you would use with select, like so:
data = data.frame(
asihckhdoydkhxiydfgfTgdsx = sample(LETTERS[1:3], 100, replace=TRUE),
a30mvxigxkghc5cdsvxvyv0ja = sample(LETTERS[1:3], 100, replace=TRUE),
value = rnorm(100)
)
# get the column...
What are the differences between double-dot “..” and triple-dot “…” in Git commit ranges?
...n Git diff commit ranges?.
See Also
Pro Git § 6.1 Git Tools - Revision Selection - Commit Ranges
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Curly braces in string in PHP
...s the code I got from one wordpress plugin
$data = $wpdb->get_results("select * from {$wpdb->prefix}download_monitor_files");
This is really handy technique for formatting complex strings.
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Changing the resolution of a VNC session in linux [closed]
... a solution using TigerVNC which is the default these days.
xrandr allows selecting the display modes (a.k.a resolutions) however
due to modelines being hard
coded
any additional modeline such as "2560x1600" or "1600x900" would need to
be added into the
code. I
think the developers who wrote the co...
How to handle click event in Button Column in Datagridview?
...ast the sender to type DataGridView, we can get the Columns collection and select the current column using e.ColumnIndex. Then check if that object is of type DataGridViewButtonColumn.
Of course, if you need to distinguish between multiple buttons per grid, you can then select based on the column n...
How to host google web fonts on my own server?
...rovide a ~420MB zip snapshot of their fonts.
You first download your font selection as a zipped package, providing you with a bunch of true type fonts. Copy them somewhere public, somewhere you can link to from your css.
On the google webfont download page, you'll find a include link like so:
http:...
How do you properly use namespaces in C++?
...mbols from the namespace.
The most secure way to use "using" is to import select symbols:
void doSomething()
{
using std::string ; // string is now "imported", at least,
// until the end of the function
string a("Hello World!") ;
std::cout << a << std::en...
HashSet versus Dictionary w.r.t searching time to find if an item exists
...value);
}
var testPoints = Enumerable.Repeat(1, TestReps).Select(_ => rand.Next()).ToArray();
var timer = new Stopwatch();
var total = 0;
timer.Restart();
for (int i = 0; i < TestReps; i++)
{
var newKey =...
Cutting the videos based on start and end time using ffmpeg
...this answer if you don't need to trim at an exact milisecond, thus it will select the closest keyframe available. That's why it's so fast, it selects the closest keyframes and takes the snippet out without the need of reencoding. However, if you do need a precise time, taking the nearest keyframe is...
In absence of preprocessor macros, is there a way to define practical scheme specific flags at proje
...BGU key work in #IF DEBUG works in debug mode and #ELSE in release mode:
Select your target,
In Build Setting tab search for "Active Compilation Condition",
Set the value of its "Debug" item to "YourKeyWord",
Use simply as follow:
#if DEBUG
print("You'r running in DEBUG mode!")
#else
prin...