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Drop data frame columns by name
...t I would like to remove from a data frame. I know that we can delete them individually using something like:
20 Answers
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Why historically do people use 255 not 256 for database field magnitudes?
...acters, what is the traditional / historic reason why? I assume it's something to do with paging / memory limits, and performance but the distinction between 255 and 256 has always confused me.
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Android Replace “…” with ellipsis character
Since AVD tools 16 I'm getting this warning:
7 Answers
7
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Observer Design Pattern vs “Listeners”
It seems to me that the Observer design pattern as described in GOF is really the same thing as Listeners found in various toolkits. Is there a difference between the concepts, or are Listeners and Observers really the same thing.
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What's the equivalent for eclipse's ALT+UP/DOWN (move line) in Visual Studio?
In Eclipse, selecting a line and pressing Alt + ↑ / ↓ will move the line up and down, a quick way to avoid copy&paste.
Is there an equivalent in Visual Studio?
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Mercurial for Beginners: The Definitive Practical Guide
Inspired by Git for beginners: The definitive practical guide.
22 Answers
22
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How to See the Contents of Windows library (*.lib)
I have a binary file - Windows static library (*.lib).
Is there a simple way to find out names of the functions and their interface from that library ?
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parseInt(null, 24) === 23… wait, what?
Alright, so I was messing around with parseInt to see how it handles values not yet initialized and I stumbled upon this gem. The below happens for any radix 24 or above.
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Margin-Top push outer div down
I have a header div as the first element in my wrapper div, but when I add a top margin to a h1 inside the header div it pushes the entire header div down. I realize this happens whenever I apply a top margin to the first visible element on a page.
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Download file of any type in Asp.Net MVC using FileResult?
...iles from my Asp.Net MVC application. But the only examples of this I can find always has to do with image files (specifying content type image/jpeg).
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