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What is the python “with” statement designed for?
...inal working directory
Here's another example that temporarily redirects sys.stdin, sys.stdout and sys.stderr to some other file handle and restores them later:
from contextlib import contextmanager
import sys
@contextmanager
def redirected(**kwds):
stream_names = ["stdin", "stdout", "stderr...
How to create id with AUTO_INCREMENT on Oracle?
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SYS_GUID returns a GUID-- a globally unique ID. A SYS_GUID is a RAW(16). It does not generate an incrementing numeric value.
If you want to create an incrementing numeric key, you'll want to create a sequence.
CREATE SE...
How can I get column names from a table in SQL Server?
...lso do it by a SQL query. Some thing like this should help:
SELECT * FROM sys.columns WHERE object_id = OBJECT_ID('dbo.yourTableName')
Or a variation would be:
SELECT o.Name, c.Name
FROM sys.columns c
JOIN sys.objects o ON o.object_id = c.object_id
WHERE o.type = 'U'
ORDER ...
Convert hex string to int in Python
How do I convert a hex string to an int in Python?
12 Answers
12
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How to get a reference to a module inside the module itself?
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import sys
current_module = sys.modules[__name__]
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Python: reload component Y imported with 'from X import Y'?
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from modulename import func
import importlib, sys
importlib.reload(sys.modules['modulename'])
from modulename import func
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Measuring function execution time in R
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Another possible way of doing this would be to use Sys.time():
start.time <- Sys.time()
...Relevent codes...
end.time <- Sys.time()
time.taken <- end.time - start.time
time.taken
Not the most elegant way to do it, compared to the answere above , but definitely a w...
Using the rJava package on Win7 64 bit with R
...(at least for me). You can check easily within R is JAVA_HOME is set with
Sys.getenv("JAVA_HOME")
If you need to have JAVA_HOME set (e.g. you need it for maven or something else), you could deactivate it within your R-session with the following code before loading rJava:
if (Sys.getenv("JAVA_HO...
How to convert List to List?
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Using Linq:
var intList = stringList.Select(s => Convert.ToInt32(s)).ToList()
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An efficient way to transpose a file in Bash
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$ time perl test.pl file >/dev/null
real 0m0.480s
user 0m0.442s
sys 0m0.026s
$ time awk -f test.awk file >/dev/null
real 0m0.382s
user 0m0.367s
sys 0m0.011s
$ time perl test.pl file >/dev/null
real 0m0.481s
user 0m0.431s
sys 0m0.022s
$ time awk -f test.a...