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Use cases for the 'setdefault' dict method
...e case: Grouping items (in unsorted data, else use itertools.groupby)
# really verbose
new = {}
for (key, value) in data:
if key in new:
new[key].append( value )
else:
new[key] = [value]
# easy with setdefault
new = {}
for (key, value) in data:
group = new.setdefault(k...
How do you query for “is not null” in Mongo?
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This will return all documents with a key called "IMAGE URL", but they may still have a null value.
db.mycollection.find({"IMAGE URL":{$exists:true}});
This will return all documents with both a key called "IMAGE URL" and a non-null value.
d...
Jquery selector input[type=text]')
I wrote a code that basically selects all input type=text element like this:
4 Answers
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System.BadImageFormatException: Could not load file or assembly (from installutil.exe)
I am trying to install a Windows service using InstallUtil.exe and am getting the error message
15 Answers
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undefined reference to boost::system::system_category() when compiling
...raries. I have the 1.46-dev Boost libraries from the Ubuntu Repository installed, but I get an error when compiling the program.
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Are types like uint32, int32, uint64, int64 defined in any stdlib header?
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This answer is wrong. All of the above are only available if an exact width type of that size (no padding) exists in the implementation. Even if not, however, the types int_leastNN_t and uint_leastNN_t for NN 8, 16, 32, and 64 must always exist. C...
How do I check if an object has a specific property in JavaScript?
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I'm really confused by the answers that have been given - most of them are just outright incorrect. Of course you can have object properties that have undefined, null, or false values. So simply reducing the property check to typeo...
How to search a string in multiple files and return the names of files in Powershell?
... large operations like that. It becomes very convoluted when you try to do all of that on one line and it is very easy to make a large mistake. I speak from experience
– Kolob Canyon
Sep 6 '18 at 15:44
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Force Java timezone as GMT/UTC
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Yep, that fine. Just one point to mention, that I actually set the user.timezone directly in code, rather then via the -D parameter.
– SyBer
Apr 13 '10 at 21:10
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Getter and Setter?
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That's not really setter and getter. Typically I need for each property different implementation of getter!
– sumid
Feb 16 '13 at 0:59
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