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Insert, on duplicate update in PostgreSQL?
...it would be much slower, because each upsert would be its' own individual call into the database.
– baash05
Mar 1 '12 at 0:27
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How to get the first column of a pandas DataFrame as a Series?
...c wasn't there yet back then. In 2016, the correct answer is Jeff's (after all he's pandas God, mind you ;-)). I'm not sure what's SO's policy regarding update of answers due to API change; I'm honestly surprised by the number of votes for this answer, didn't think it was that useful to people...
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How to dynamic new Anonymous Class?
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All you're doing is saying that dynamic properties are not identical to strongly-typed properties. This is trivially true.
– Steven Sudit
Sep 18 '10 at 2:31
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How to download image from url
...d content is not a known image type.
Check this reference on MSDN to find all format available.
Here are reference to WebClient and Bitmap.
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Defining a function with multiple implicit arguments in Scala
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They must all go in one parameter list, and this list must be the last one.
def myfun(arg:String)(implicit p1: String, p2:Int)={}
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Do declared properties require a corresponding instance variable?
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In your interface, you can formally declare an instance variable between the braces, or via @property outside the braces, or both. Either way, they become attributes of the class. The difference is that if you declare @property, then you can implement usin...
Difference between “module.exports” and “exports” in the CommonJs Module System
...ns to be set to module.exports.
At the end of your file, node.js will basically 'return' module.exports to the require function. A simplified way to view a JS file in Node could be this:
var module = { exports: {} };
var exports = module.exports;
// your code
return module.exports;
If you set a...
Checking if a double (or float) is NaN in C++
...nly if f is NaN.
Note that, as some comments below have pointed out, not all compilers respect this when optimizing code.
For any compiler which claims to use IEEE floating point, this trick should work. But I can't guarantee that it will work in practice. Check with your compiler, if in doubt.
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What is the common header format of Python files?
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Its all metadata for the Foobar module.
The first one is the docstring of the module, that is already explained in Peter's answer.
How do I organize my modules (source files)? (Archive)
The first line of each file shoud be #!/us...
Complete Working Sample of the Gmail Three-Fragment Animation Scenario?
...at I'll refer to as "the Gmail three-fragment animation" scenario. Specifically, we want to start with two fragments, like this:
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