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Simplest way to profile a PHP script
...connect_to_db();
prof_flag("Perform query");
// Get all the data
$select_query = "SELECT * FROM data_table";
$result = mysql_query($select_query);
prof_flag("Retrieve data");
$rows = array();
$found_data=false;
while($r = mysql_fetch_assoc($result))
{
$found_data=tru...
How to drop columns by name in a data frame
..."z","u"))]
x y
1 1 2
2 2 3
3 3 4
4 4 5
5 5 6
Or, much simpler, use the select argument of the subset function : you can then use the - operator directly on a vector of column names, and you can even omit the quotes around the names !
R> subset(df, select=-c(z,u))
x y
1 1 2
2 2 3
3 3 4
4 4 ...
Managing CSS Explosion
...he start of each line when writing TOCs, it just makes it more annoying to select the text.
/* Table of Contents
- - - - - - - - -
Header stuff
Body Stuff
Some other junk
- - - - - - - - -
*/
...
/* Header Stuff
*/
...
/* Body Stuff
*/
Write comments with or within the rules, ...
How to collapse all methods in Xcode?
...upport for folding blocks of code from the folding ribbon, from structured selection, or from the
Menubar ► Editor ► Code Folding ► Fold menu item
Look at this snapshot:
Code folding was disabled in Xcode 9 beta 1, which is working now, in Xcode 9 Beta5 according to beta relea...
How do RVM and rbenv actually work?
... practical difference between RVM and rbenv is when the version of Ruby is selected.
rbenv:
rbenv adds a shim to the start of your path, a command with the same name as Ruby. When you type ruby at a command line the shim is run instead (because it is also called "ruby" and comes first in the path)...
How to add directory to classpath in an application run profile in IntelliJ IDEA?
...e F12)
click on the dependencies tab
Click the "+" button on the right and select "Jars or directories..."
Find your path and click OK
In the dialog with "Choose Categories of Selected File", choose Classes (even if it's properties), press OK and OK again
You can now run your application and it will...
Select values from XML field in SQL Server 2008
...
Given that the XML field is named 'xmlField'...
SELECT
[xmlField].value('(/person//firstName/node())[1]', 'nvarchar(max)') as FirstName,
[xmlField].value('(/person//lastName/node())[1]', 'nvarchar(max)') as LastName
FROM [myTable]
...
minimum double value in C/C++
...tion just has to work around it. See the floating-point model in 5.2.4.2.2 Characteristics of floating types <float.h> p2 of C99 (may have been moved elsewhere since then).
– user743382
Nov 10 '14 at 22:23
...
How to read a file into a variable in shell?
...ther answers so far:
Trailing newline removal from command expansion
NUL character removal
Trailing newline removal from command expansion
This is a problem for the:
value="$(cat config.txt)"
type solutions, but not for read based solutions.
Command expansion removes trailing newlines:
S="...
JavaScript Editor Plugin for Eclipse [duplicate]
...ript files:
Open Eclipse -> Go to "Help" -> "Install New Software"
Select the repository for your version of Eclipse. I have Juno so I selected http://download.eclipse.org/releases/juno
Expand "Programming Languages" -> Check the box next to "JavaScript Development Tools"
Click "Next" -&g...