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“Large data” work flows using pandas
... one contains different fields, or do they have some records per file with all of the fields in each file?
Do you ever select subsets of rows (records) based on criteria (e.g. select the rows with field A > 5)? and then do something, or do you just select fields A, B, C with all of the records (a...
Django Rest Framework: Dynamically return subset of fields
...verride the serializer __init__ method and set the fields attribute dynamically, based on the query params. You can access the request object throughout the context, passed to the serializer.
Here is a copy&paste from Django Rest Framework documentation example on the matter:
from rest_framew...
capturing self strongly in this block is likely to lead to a retain cycle
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Good answer, but I take small issue with you saying: “you can't refer to self or properties on self from within a block that will be strongly retained by self.” This is not strictly true. Please see my answer below. Better to say, “you must take...
Undo svn add without reverting local edits
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The final command always creates an extra directory level, i.e. ending up with YOURDIR/YOURDIR/, although I think the issue is in the initial backup command creating YOURDIR.bak/YOURDIR/.
– James
Jan 1 '18 at 19:37
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How to exit from Python without traceback?
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If sys.exit() is called in "main program stuff", the code above throws away the value passed to sys.exit. Notice that sys.exit raises SystemExit and the variable "e" will contain the exit code.
– bstpierre
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How to check visibility of software keyboard in Android?
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Some keyboards, some of the time, have an extra row of custom keys on top (for instance, predicted words). These are apparently not part of the keyboard itself, since using the getLastKeyboardHeightInPx() does not include the height of that row. Do you know of a way ...
What is %2C in a URL?
...mma (,).
You should use your language's URL encoding methods when placing strings in URLs.
You can see a handy list of characters with man ascii. It has this compact diagram available for mapping hexadecimal codes to the character:
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0: 0 @ P ` p
1:...
Debugging in Clojure? [closed]
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There's also dotrace, which allows you to look at the inputs and outputs of selected functions.
(use 'clojure.contrib.trace)
(defn fib[n] (if (< n 2) n (+ (fib (- n 1)) (fib (- n 2)))))
(dotrace [fib] (fib 3))
produces the output:
TRACE t4425: (f...
Specifying column name in a “references” migration
...eferences :col_name, references: other_table_name works without installing extra gems.
– Qqwy
Sep 9 '19 at 14:26
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How to ignore user's time zone and force Date() use specific time zone
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A Date object's underlying value is actually in UTC. To prove this, notice that if you type new Date(0) you'll see something like: Wed Dec 31 1969 16:00:00 GMT-0800 (PST). 0 is treated as 0 in GMT, but .toString() method shows the local time.
Big note, UTC stands ...