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Extract a dplyr tbl column as a vector
... to get one column of a dplyr tbl as a vector, from a tbl with database back-end (i.e. the data frame/table can't be subset directly)?
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Is there a ceiling equivalent of // operator in Python?
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Machavity♦
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answered Feb 11 '13 at 22:35
Charles SalviaChar...
What's the point of malloc(0)?
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Reed CopseyReed Copsey
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undefined method `source_index' for Gem:Module (NoMethodError)
...an older Rails app from REE 1.8.7 to 1.9.3-p385. Oddly, Ruby 1.9.3-p327 works just fine. What it came down to was ruby-1.9.3-p385 had installed RubyGems version 2.0.2 for me, and 1.9.3-p327 has RubyGems v1.8.23 installed.
Gem.source_index has been deprecated for a while, but since Rails 2.3 is not ...
How to stop event propagation with inline onclick attribute?
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Use event.stopPropagation().
<span onclick="event.stopPropagation(); alert('you clicked inside the header');">something inside the header</span>
For IE: window.event.cancelBubble = true
<span onclick="window.event.cancelBubble = true; alert('you click...
Android SDK on a 64-bit linux machine
Is it possible to develop using the Android SDK on a 64-bit linux machine. The available SDK downloads seem to be just for 32-bit versions of Linux.
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How to distinguish mouse “click” and “drag”
I use jQuery.click to handle the mouse click event on Raphael graph, meanwhile, I need to handle mouse drag event, mouse drag consists of mousedown , mouseup and mousemove in Raphael.
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What is a good regular expression to match a URL? [duplicate]
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DaveoDaveo
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Specifying an Index (Non-Unique Key) Using JPA
... eg email as having an index using JPA annotations. We need a non-unique key on email because there are literally millions of queries on this field per day, and its a bit slow without the key.
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How do you render primitives as wireframes in OpenGL?
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glPolygonMode( GL_FRONT_AND_BACK, GL_LINE );
to switch on,
glPolygonMode( GL_FRONT_AND_BACK, GL_FILL );
to go back to normal.
Note that things like texture-mapping and lighting will still be applied to the wireframe lines if they're enabled, which ca...