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List distinct values in a vector in R
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You can also use the sqldf package in R.
Z <- sqldf('SELECT DISTINCT tablename.columnname FROM tablename ')
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Diagnosing Memory Leaks - Allowed memory size of # bytes exhausted
...ode to trawl through to find it, I'm afraid. The simplest instrument is to selectively place calls to memory_get_usage and narrow it down to where the code leaks. You can also use xdebug to create a trace of the code. Run the code with execution traces and show_mem_delta.
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Can I add color to bootstrap icons only using CSS?
...) your cursor looks like an oversized capital "I" character, it's used for selecting text. In CSS it's referred to as cursor: text;. It's also known as "I-beam".
– Dai
Sep 12 '12 at 1:47
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Is there type Long in SQLite?
...tant: retrieve the value from cursor as LONG
Cursor cursor = db.rawQuery("SELECT * FROM " + TABLE_A, null);
long value = cursor.getLong(0);
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Nginx serves .php files as downloads, instead of executing them
...an't understand a .php file (or for that matter any extension apart from a select few like .html, .js etc. which are static files)
Thus in order to run other kinds of files we need something that sits between nginx and the application (here the php application). This is where common gateway interfac...
Are nested HTML comments possible?
...ere. Its parent element has to be either the <body> element or a few select others.
– John E
Jan 17 '19 at 14:09
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Most common C# bitwise operations on enums
...g)(ulong)flags : Convert.ToInt64(flags)) & (1L << bit)) != 0)
.Select(bit => Enum.ToObject(flags.GetType(), 1L << bit))`
Enums.NET flags.GetFlags()
I'm trying to get these improvements incorporated into .NET Core and maybe eventually the full .NET Framework. You can check o...
How to apply CSS to iframe?
... @jmalais Just replace #iframe with #<id> or even iframe to select all iframes
– Zeb McCorkle
Aug 13 '14 at 19:01
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How do you disable the unused variable warnings coming out of gcc in 3rd party code I do not wish to
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If you're using gcc and want to disable the warning for selected code, you can use the #pragma compiler directive:
#pragma GCC diagnostic push
#pragma GCC diagnostic ignored "-Wunused-variable"
( your problematic library includes )
#pragma GCC diagnostic pop
For code you contro...
How to get ALL child controls of a Windows Forms form of a specific type (Button/Textbox)?
...ar controls = control.Controls.Cast<Control>();
return controls.SelectMany(ctrl => GetAll(ctrl,type))
.Concat(controls)
.Where(c => c.GetType() == type);
}
To test it in the form load event I wanted a count of all control...