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Python nested functions variable scoping [duplicate]
...his line:
_total += PRICE_RANGES[key][0]
The documentation about Scopes and Namespaces says this:
A special quirk of Python is that – if no global statement is in effect – assignments to names always go into the innermost scope. Assignments do not copy data — they just bind names to ob...
How to test valid UUID/GUID?
...e is the NIL UUID, noted here. The following regex takes this into account and will return a match for a NIL UUID. See below for a UUID which only accepts non-NIL UUIDs. Both of these solutions are for versions 1 to 5 (see the first character of the third block).
Therefore to validate a UUID...
/^...
Postgres: INSERT if does not exist already
...
Postgres 9.5 (released since 2016-01-07) offers an "upsert" command, also known as an ON CONFLICT clause to INSERT:
INSERT ... ON CONFLICT DO NOTHING/UPDATE
It solves many of the subtle problems you can run into when using concurrent operation, which some other answers propose.
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Reading specific lines only
... loop to read a file, but I only want to read specific lines, say line #26 and #30. Is there any built-in feature to achieve this?
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scp with port number specified
...lt
The lowercase p switch is used with scp for the preservation of times and modes.
Here is an excerpt from scp's man page with all of the details concerning the two switches, as well as an explanation of why uppercase P was chosen for scp:
-P port Specifies the port to connect to on the r...
Linux vi arrow keys broken in insert mode
...s don't work in vi in insert mode at home, they just each insert a newline and a capital letter, like 'A'. Is there a way to fix that?
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Getting distance between two points based on latitude/longitude
I tried implementing this formula: http://andrew.hedges.name/experiments/haversine/
The aplet does good for the two points I am testing:
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jquery.validate.unobtrusive not working with dynamic injected elements
... with the latest MVC RC? or they just fixed that?
– xandy
Jan 24 '11 at 10:03
1
When using the co...
How do I reverse an int array in Java?
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And I would like to put validData.length / 2 part to the outside of the for-loop.
– Jin Kwon
Mar 10 '14 at 3:28
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Pandas conditional creation of a series/dataframe column
...color'] = np.where(df['Set']=='Z', 'green', 'red')
For example,
import pandas as pd
import numpy as np
df = pd.DataFrame({'Type':list('ABBC'), 'Set':list('ZZXY')})
df['color'] = np.where(df['Set']=='Z', 'green', 'red')
print(df)
yields
Set Type color
0 Z A green
1 Z B green
2 ...