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Where can I learn how to write C code to speed up slow R functions? [closed]
What's the best resource for learning how to write C code for use with R? I know about the system and foreign language interfaces section of R extensions, but I find it pretty hard going. What are good resources (both online and offline) for writing C code for use with R?
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What is the most efficient/elegant way to parse a flat table into a tree?
... all popular SQL databases support recursive queries in standard syntax.
WITH RECURSIVE MyTree AS (
SELECT * FROM MyTable WHERE ParentId IS NULL
UNION ALL
SELECT m.* FROM MyTABLE AS m JOIN MyTree AS t ON m.ParentId = t.Id
)
SELECT * FROM MyTree;
I tested recursive queries in MySQL 8.0...
Converting a view to Bitmap without displaying it in Android?
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there is a way to do this. you have to create a Bitmap and a Canvas and call view.draw(canvas);
here is the code:
public static Bitmap loadBitmapFromView(View v) {
Bitmap b = Bitmap.createBitmap( v.getLayoutParams().width, v.getLayoutParams().height, Bitmap.Config.ARG...
How does python numpy.where() work?
I am playing with numpy and digging through documentation and I have come across some magic. Namely I am talking about numpy.where() :
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What is the intended use-case for git stash?
...work on branch A and suddenly need to work on branch B before being ready with a commit on branch A, I stash my changes on A, checkout B, do my work there, then checkout A and apply the stash.
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how to break the _.each function in underscore.js
I'm looking for a way to stop iterations of underscore.js _.each() method, but can't find the solution. jQuery .each() can break if you do return false .
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How can I override Bootstrap CSS styles?
I need to modify bootstrap.css to fit my website. I feel it's better to create a separate custom.css file instead of modifying bootstrap.css directly, one reason being that should bootstrap.css get an update, I'll suffer trying to re-include all my modifications. I'll sacrifice some load tim...
Test if string is a guid without throwing exceptions?
... class identifier</param>
/// <returns>
/// Positive or zero if class identifier was obtained successfully
/// Negative if the call failed
/// </returns>
[DllImport("ole32.dll", CharSet = CharSet.Unicode, ExactSpelling = true, PreserveSig = t...
Why does Java have transient fields?
...ike to a file) process.
From the Java Language Specification, Java SE 7 Edition, Section 8.3.1.3. transient Fields:
Variables may be marked transient to
indicate that they are not part of the
persistent state of an object.
For example, you may have fields that are derived from other field...
Most efficient method to groupby on an array of objects
...follow
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edited Mar 26 at 21:11
answered Jan 20 '16 at 2:02
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