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Creating a new dictionary in Python
... Is there any difference between dict() and {}? Or do people just prefer one over the other?
– Matt
Mar 2 '12 at 17:13
53
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How to drop columns by name in a data frame
...d this option to avoid the conversion to an atomic vector if there is only one column left
Second, quicker to write, you can directly assign NULL to the columns you want to remove:
data[c("iden", "name", "x_serv", "m_serv")] <- list(NULL) # You need list() to respect the target structure.
Fi...
MySQL INSERT INTO table VALUES.. vs INSERT INTO table SET
... @Pacerier Such as? The only problem I see is a portability one (which, in many contexts doesn't really matter); am I missing something?
– Mark Amery
Jan 29 '13 at 13:56
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How to get unique device hardware id in Android? [duplicate]
...he unique device ID in Android which cannot be changed when performing a phone reset or OS update?
3 Answers
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Why are Python lambdas useful? [closed]
I'm trying to figure out Python lambdas. Is lambda one of those "interesting" language items that in real life should be forgotten?
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Can I change the fill color of an svg path with CSS?
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@RicardoZea One caveat to that: you can include an object from an external SVG file with <use href="external.svg#objId" /> and your local CSS will still apply to some degree.
– Ken Bellows
Oct...
How do I merge two dictionaries in a single expression in Python (taking union of dictionaries)?
...es
z.update(y) # modifies z with y's keys and values & returns None
return z
and now:
z = merge_two_dicts(x, y)
In Python 3.9.0a4 or greater (final release date approx October 2020): PEP-584, discussed here, was implemented to further simplify this:
z = x | y # NOTE: 3.9+ ...
How to convert an Stream into a byte[] in C#? [duplicate]
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A bunch of concerns are mixed together in one big method. Yes, it all has to be done, but not all in one function. There's the growable byte array and there's the stream reading. Much easier to get right if they're separated.
– Daniel Earwicker
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“implements Runnable” vs “extends Thread” in Java
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One minor advantage of Runnable is that, if in certain circumstances you don't care about, or don't want to use threading, and you just want to execute the code, you have the option to simply call run(). e.g. (very handwavy)...
'AND' vs '&&' as operator
...ND and OR, you'll eventually get tripped up by something like this:
$this_one = true;
$that = false;
$truthiness = $this_one and $that;
Want to guess what $truthiness equals?
If you said false... bzzzt, sorry, wrong!
$truthiness above has the value true. Why? = has a higher precedence than a...