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Viewing all defined variables [duplicate]
...ython shell. What I want to have is Matlab style listout where you can see all the variables that have been defined up to a point (so I know which names I've used, their values and such).
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What is the most efficient/elegant way to parse a flat table into a tree?
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Now that MySQL 8.0 supports recursive queries, we can say that all popular SQL databases support recursive queries in standard syntax.
WITH RECURSIVE MyTree AS (
SELECT * FROM MyTable WHERE ParentId IS NULL
UNION ALL
SELECT m.* FROM MyTABLE AS m JOIN MyTree AS t ON m.ParentI...
How to save as a new file and keep working on the original one in Vim?
...} So, :sav is the shortener for :saveas. Whereas, :w is the shortcut for :[range]w[rite][!] [++opt] {file}. And everything is in the manual, just few lines above/below.
– Atcold
Oct 20 '14 at 19:22
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How to initialize all members of an array to the same value?
... array in C (not C++ if that makes a difference). I want to initialize all members of the same value.
23 Answers
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How can I map True/False to 1/0 in a Pandas DataFrame?
...rectly on Frames
In [104]: df = DataFrame(dict(A = True, B = False),index=range(3))
In [105]: df
Out[105]:
A B
0 True False
1 True False
2 True False
In [106]: df.dtypes
Out[106]:
A bool
B bool
dtype: object
In [107]: df.astype(int)
Out[107]:
A B
0 1 0
1 1 0
2 ...
Get all object attributes in Python? [duplicate]
Is there a way to get all attributes/methods/fields/etc. of an object in Python?
4 Answers
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How does __proto__ differ from constructor.prototype?
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I've been trying to wrap my head around this recently and finally came up with this "map" that I think sheds full light over the matter
http://i.stack.imgur.com/KFzI3.png
I know I'm not the first one making this up but it was more interesting figuring it out that finding it :-). An...
SQL NVARCHAR and VARCHAR Limits
...hat all string literals (or at least those with lengths in the 4001 - 8000 range) are prefaced with N.
To avoid the first issue change the assignment from
DECLARE @SQL NVARCHAR(MAX);
SET @SQL = 'Foo' + 'Bar' + ...;
To
DECLARE @SQL NVARCHAR(MAX) = '';
SET @SQL = @SQL + N'Foo' + N'Bar'
so that an N...
Relative imports in Python 2.7
... not determine what package Python thinks it is in. That depends, additionally, on how you load the file into Python (by running or by importing).
There are two ways to load a Python file: as the top-level script, or as a
module. A file is loaded as the top-level script if you execute it directl...
Going to a specific line number using Less in Unix
... '320123'p filename
This will print line number 320123.
If you want a range then you can do -
sed -n '320123,320150'p filename
If you want from a particular line to the very end then -
sed -n '320123,$'p filename
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