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How update the _id of one MongoDB Document?
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A fun issue with this appears if some field on that document has a unique index. In that situation, your example will fail because a document cannot be inserted with a duplicate value in a unique indexed field. You could fix ...
How to track down log4net problems
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Just a note I found the fun way. Make sure the <configSections></configSections> is the first entry under <configuration>. Otherwise you end up with an error.
– Nick
Jul 25 '17 at 13:59
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How to convert a data frame column to numeric type?
... you want to convert to numeric. I suggest that you should apply transform function in order to complete your task.
Now I'm about to demonstrate certain "conversion anomaly":
# create dummy data.frame
d <- data.frame(char = letters[1:5],
fake_char = as.character(1:5),
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When is a CDATA section necessary within a script tag?
...answered Sep 20 '09 at 9:05
user123444555621user123444555621
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What's the best way to detect a 'touch screen' device using JavaScript?
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As Modernizr doesn't detect IE10 on Windows Phone 8/WinRT, a simple, cross-browser solution is...
What is the difference between 'my' and 'our' in Perl?
...ariables. You can see that in the following program: package Foo; our $x = 123; package Bar; say $x;. If you want to "declare" a package variable, you need to use use vars qw( $x );. our $x; declares a lexically-scoped variable that is aliased to the same-named variable in the package in which the o...
select * vs select column
... order; all his code broke as soon as someone else changed the table. What fun we had.
– Paul McKenzie
Jul 5 '10 at 15:06
7
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How do I make a simple makefile for gcc on Linux?
...en't that bad. Sure, they feel awful, and getting used to them is about as fun as forcing your head through a brick wall, but they do work, and they're well developed, and they'll cover most of your bases as far as portability, and will make your life a lot easier in the end once you get used to the...
Get Base64 encode file-data from Input Form
...g stuff (up to the first ,), but that's no biggie. This would take all the fun out though.
The hard way:
If you want to try it the hard way (or it doesn't work), look at readAsArrayBuffer(). This will give you a Uint8Array and you can use the method specified. This is probably only useful if you w...
How to do constructor chaining in C#
... {
}
}
then:
Foo a = new Foo(), b = new Foo(456,"def"), c = new Foo(123), d = new Foo("abc");
Note also:
you can chain to constructors on the base-type using base(...)
you can put extra code into each constructor
the default (if you don't specify anything) is base()
For "why?":
code r...