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The difference between bracket [ ] and double bracket [[ ]] for accessing the elements of a list or
...urn the ith sequential element of x.
For lists, one generally uses [[ to select any single element, whereas [ returns a list of the selected elements.
The [[ form allows only a single element to be selected using integer or character indices, whereas [ allows indexing by vectors. Note though tha...
How do I create test and train samples from one dataframe with pandas?
...
scikit learn's train_test_split is a good one.
from sklearn.model_selection import train_test_split
train, test = train_test_split(df, test_size=0.2)
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HTML - Display image after selecting filename [duplicate]
I have a form that allows me with
3 Answers
3
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When should one use final for method parameters and local variables?
...y. In particular, Java function signatures are hard enough to fit into 80 characters as it is without adding six more per argument!
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Show constraints on tables command
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Simply query the INFORMATION_SCHEMA:
USE INFORMATION_SCHEMA;
SELECT TABLE_NAME,
COLUMN_NAME,
CONSTRAINT_NAME,
REFERENCED_TABLE_NAME,
REFERENCED_COLUMN_NAME
FROM KEY_COLUMN_USAGE
WHERE TABLE_SCHEMA = "<your_database_name>"
AND TABLE_NAME = "<y...
Does Java have something like C#'s ref and out keywords?
...his should be expanded on some. You can only pass primitives (int, short, char, etc.) as value. And no, there is no out.
– Corey Sunwold
May 10 '10 at 21:26
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How to get .app file of a xcode application
...t-clicking it in the Products directory in the source pane on the left and selecting "Show in Finder".
– Akilan Arasu
Aug 11 '16 at 11:38
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Return array in a function
...llarr(int arr[]){
array[0] = 10;
array[1] = 5;
}
int main(int argc, char* argv[]){
int arr[] = { 1,2,3,4,5 };
// arr[0] == 1
// arr[1] == 2 etc
int result = fillarr(arr);
// arr[0] == 10
// arr[1] == 5
return 0;
}
I suggest you might want to consider putting a leng...
Exit single-user mode
...tabase in MULTI_USER mode.
USE master
GO
DECLARE @kill varchar(max) = '';
SELECT @kill = @kill + 'KILL ' + CONVERT(varchar(10), spid) + '; '
FROM master..sysprocesses
WHERE spid > 50 AND dbid = DB_ID('<Your_DB_Name>')
EXEC(@kill);
GO
SET DEADLOCK_PRIORITY HIGH
ALTER DATABASE [<Your_DB...
Select random lines from a file
...e point is you can keep some lines in memory with shuffle to do the random selection of what to output. Sort is going to sort the entire file, regardless of what your needs are.
– Rubens
Sep 25 '14 at 2:01
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