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How do I install Python OpenCV through Conda?
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edited Jun 30 '17 at 10:00
Quanlong
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Is there a standard naming convention for git tags? [closed]
I've seen a lot of projects using v1.2.3 as the naming convention for tags in git. I've also seen some use 1.2.3 . Is there an officially endorsed style, or are there any good arguments for using either?
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find vs find_by vs where
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JohnJohn
3,16622 gold badges2020 silver badges3535 bronze badges
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Turning a Comma Separated string into individual rows
...9, '18,20,22'
INSERT Testdata SELECT 2, 8, '17,19'
INSERT Testdata SELECT 3, 7, '13,19,20'
INSERT Testdata SELECT 4, 6, ''
INSERT Testdata SELECT 9, 11, '1,2,3,4'
The query
;WITH tmp(SomeID, OtherID, DataItem, String) AS
(
SELECT
SomeID,
OtherID,
LEFT(String, CHAR...
Delete column from pandas DataFrame
...01
cs95
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answered Nov 21 '12 at 3:12
Wes McKinneyW...
Converting between datetime, Timestamp and datetime64
...tetime.utcnow()
>>> dt
datetime.datetime(2012, 12, 4, 19, 51, 25, 362455)
>>> dt64 = np.datetime64(dt)
>>> ts = (dt64 - np.datetime64('1970-01-01T00:00:00Z')) / np.timedelta64(1, 's')
>>> ts
1354650685.3624549
>>> datetime.utcfromtimestamp(ts)
datetime.da...
Getting SyntaxError for print with keyword argument end=' '
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Are you sure you are using Python 3.x? The syntax isn't available in Python 2.x because print is still a statement.
print("foo" % bar, end=" ")
in Python 2.x is identical to
print ("foo" % bar, end=" ")
or
print "foo" % bar, end=" "
i.e. as a call to...
Insert, on duplicate update in PostgreSQL?
... the_table (id, column_1, column_2)
VALUES (1, 'A', 'X'), (2, 'B', 'Y'), (3, 'C', 'Z')
ON CONFLICT (id) DO UPDATE
SET column_1 = excluded.column_1,
column_2 = excluded.column_2;
Searching postgresql's email group archives for "upsert" leads to finding an example of doing what you poss...
How to use filter, map, and reduce in Python 3
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352
You can read about the changes in What's New In Python 3.0. You should read it thoroughly when...
Algorithms based on number base systems? [closed]
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39
Chris Okasaki has a very good chapter in his book Purely Functional Data Structures that discus...