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Calculate difference in keys contained in two Python dictionaries
Suppose I have two Python dictionaries - dictA and dictB . I need to find out if there are any keys which are present in dictB but not in dictA . What is the fastest way to go about it?
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Java associative-array
How can I create and fetch associative arrays in Java like I can in PHP?
15 Answers
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Oracle: how to UPSERT (update or insert into a table?)
...swered Oct 27 '08 at 11:12
Tony AndrewsTony Andrews
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How to use the 'sweep' function
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sweep() is typically used when you operate a matrix by row or by column, and the other input of the operation is a different value for each row / column. Whether you operate by row or column is defined by MARGIN, as for apply(). The values used for what I called "the other input" is defined by STA...
Is there a /dev/null on Windows?
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I think you want NUL, at least within a command prompt or batch files.
For example:
type c:\autoexec.bat > NUL
doesn't create a file.
(I believe the same is true if you try to create a file programmatically, but I haven't tried it.)
In PowerShell, you want $nu...
Unicode character as bullet for list-item in CSS
...probably go for an image background, they're much more efficient versatile and cross-browser-friendly.
Here's an example:
<style type="text/css">
ul {list-style:none;} /* you should use a css reset too... ;) */
ul li {background:url(images/icon_star.gif) no-repeat 0 5px;}
</style>
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Age from birthdate in python
How can I find an age in python from today's date and a persons birthdate? The birthdate is a from a DateField in a Django model.
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What's the difference between “squash” and “fixup” in Git/Git Extension?
...the commit log message begins with "squash! ..." (or "fixup!
..."), and there is a commit whose title begins with the same ...,
automatically modify the todo list of rebase -i so that the commit
marked for squashing comes right after the commit to be modified,
and change ...
What is AF_INET, and why do I need it?
I'm getting started on socket programming, and I keep seeing this AF_INET .
5 Answers
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Why `null >= 0 && null
...utine that increments the value of a variable by 1 if its type is number and assigns 0 to the variable if not, where the variable is initially null or undefined .
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