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Replacing column values in a pandas DataFrame
...a column (the second 'female' in your w['female']['female']) doesn't mean "select rows where the value is 'female'". It means to select rows where the index is 'female', of which there may not be any in your DataFrame.
shar...
Is it Linq or Lambda?
...= from item in _List
where item.Value == 1
select item;
This is also LINQ (using method syntax):
var _Results = _List.Where(x => x.Value == 1);
It's interesting to note that both of these flavors will end up producing the exact same code. The compiler offers y...
JPA eager fetch does not join
...
JPA doesn't provide any specification on mapping annotations to select fetch strategy. In general, related entities can be fetched in any one of the ways given below
SELECT => one query for root entities + one query for related mapped entity/collection of each root entity = (n+1) que...
Replace selector images programmatically
I have an ImageView that has a drawable image resource set to a selector. How do I programmatically access the selector and change the images of the highlighted and non-highlighted state?
...
How to perform a mysqldump without a password prompt?
...and in no case the root user. It can be done like this: GRANT LOCK TABLES, SELECT ON *.* TO 'BACKUPUSER'@'%' IDENTIFIED BY 'PASSWORD';
– gadjou
Feb 21 '17 at 8:34
...
Repeat String - Javascript
...y. Instead of creating an array, filling it, and joining it with an empty char, just create an array of the proper length, and join it with your desired string. Same result, less process!
String.prototype.repeat = function( num )
{
return new Array( num + 1 ).join( this );
}
alert( "string t...
How do you copy the contents of an array to a std::vector in C++ without looping?
...ven when a function expects c-style arrays you can use vectors:
vector<char> v(50); // Ensure there's enough space
strcpy(&v[0], "prefer vectors to c arrays");
Hope that helps someone out there!
share
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How to link a Facebook app with an existing fan page
...roducts").
Change your page name to mach your App name.
Go to your App and select "App Details"
Under "Contact Info" you will find "App Page". There you will be able to create a new page or if all went well, select your page from a list.
I found the info in the little question-mark next to "App pa...
Fluent and Query Expression — Is there any benefit(s) of one over other?
...me in fullNames
from name in fullName.Split()
orderby fullName, name
select name + " came from " + fullName;
Now compare this to the same thing in method syntax:
var query = fullNames
.SelectMany (fName => fName.Split().Select (name => new { name, fName } ))
.OrderBy (x => x.fN...
Why do you create a View in a database?
...e a View in their database? Why not just run a normal stored procedure or select?
25 Answers
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