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Extracting specific columns in numpy array
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I assume you wanted columns 1 and 9?
To select multiple columns at once, use
X = data[:, [1, 9]]
To select one at a time, use
x, y = data[:, 1], data[:, 9]
With names:
data[:, ['Column Name1','Column Name2']]
You can get the names from data.dtype.names…
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Apply function to all elements of collection through LINQ [duplicate]
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@BKSpurgeon: Select is a projection: 1) it's lazily evaluated; just calling it won't do anything. 2) Select produces a result - ForEach doesn't.
– Jon Skeet
Mar 20 '17 at 9:24
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Uniq by object attribute in Ruby
What's the most elegant way to select out objects in an array that are unique with respect to one or more attributes?
14 An...
How do I get the “id” after INSERT into MySQL database with Python?
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Does not works with duplicated records using insert, select and where.
– e-info128
Oct 27 '18 at 19:20
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Linq to SQL how to do “where [column] in (list of values)”
...CodeData>()
where codeIDs.Contains(codeData.CodeId)
select codeData;
But you might as well do that in dot notation:
var foo = channel.AsQueryable<CodeData>()
.Where(codeData => codeIDs.Contains(codeData.CodeId));
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Is there a shortcut in Eclipse to Re-run the most recently launched program?
...running and debugging applications has been simplified to run or debug the selected file or active editor.
When the selected resource (or active editor) is not executable, users can opt to launch the associated project or re-launch the previous launch.
These settings are managed on the Run/D...
In a storyboard, how do I make a custom cell for use with multiple controllers?
... = [controller.tableView indexPathForCell:self];
[controller.tableView selectRowAtIndexPath:path animated:NO scrollPosition:UITableViewScrollPositionNone];
[controller performSegueWithIdentifier:@"FinishedTask" sender:controller];
[super touchesEnded:touches withEvent:event];
}
@end
I...
Printing the value of a variable in SQL Developer
...utput).
Press the "+" button at the top of the Dbms Output window and then select an open database connection in the dialog that opens.
In SQL*Plus:
SET SERVEROUTPUT ON
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Is #pragma once part of the C++11 standard?
...ifferent developments, the obvious solution is
to generate a lot of random characters for the include guard
when you create it. (A good editor can be set up to do this for
you whenever you open a new header.) But even without this,
I've yet to encounter any problems with conflicts between
librarie...
Map and Reduce in .NET
...ons. C# 3.5 and Linq already has it albeit under different names.
Map is Select:
Enumerable.Range(1, 10).Select(x => x + 2);
Reduce is Aggregate:
Enumerable.Range(1, 10).Aggregate(0, (acc, x) => acc + x);
Filter is Where:
Enumerable.Range(1, 10).Where(x => x % 2 == 0);
https://www...