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What Automatic Resource Management alternatives exist for Scala?
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For now Scala 2.13 has finally supported: try with resources by using Using :), Example:
val lines: Try[Seq[String]] =
Using(new BufferedReader(new FileReader("file.txt"))) { reader =>
Iterator.unfold(())(_ => Option(reader.readLine()).ma...
Access an arbitrary element in a dictionary in Python
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for a non-destructive popitem you can make a (shallow) copy: key, value = dict(d).popitem()
– Pelle
Jan 31 '18 at 10:35
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Saving a Numpy array as an image
... Remember to scale the values to the right range for PNG, usually 0..255. The value ranges in neural networks are frequently 0..1 or -1..1.
– Tomáš Gavenčiak
Mar 31 '18 at 18:49
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How can jQuery deferred be used?
... // or may not have been retrieved using an
// XHR request.
});
Basically, if the value has already been requested once before it's returned immediately from the cache. Otherwise, an AJAX request fetches the data and adds it to the cache. The $.when/.then doesn't care about any of this; all ...
How to delete or add column in SQLITE?
...upports a limited subset of ALTER TABLE. The ALTER TABLE command in SQLite allows the user to rename a table or to add a new column to an existing table. It is not possible to rename a column, remove a column, or add or remove constraints from a table.
You can:
create new table as the one you ar...
How to set environment variables in Jenkins?
...ajorVersion" | python -c 'import sys,re,os; print("VERSION_NUMBER="+re.findall(r"[\d+\.]+", sys.stdin.read())[0]+os.environ["BUILD_NUMBER"])'
– kenny_k
Jun 19 '15 at 6:52
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How to elegantly ignore some return values of a MATLAB function?
... return value from a function without having to create dummy variables for all n-1 return values before it?
8 Answers
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“is” operator behaves unexpectedly with integers
...3):
The current implementation keeps an
array of integer objects for all
integers between -5 and 256, when you
create an int in that range you
actually just get back a reference to
the existing object. So it should be
possible to change the value of 1. I
suspect the behaviour of Py...
What are the advantages of NumPy over regular Python lists?
... Python objects, at least 4 bytes per pointer plus 16 bytes for even the smallest Python object (4 for type pointer, 4 for reference count, 4 for value -- and the memory allocators rounds up to 16). A NumPy array is an array of uniform values -- single-precision numbers takes 4 bytes each, double-pr...
Delete files older than 10 days using shell script in Unix [duplicate]
... these! Once, using a command very much like this in a cron job, I accidentally deleted every file on my production mail server older than 10 days, which I can tell you was no fun to recover from.
– DSimon
May 28 '14 at 20:00
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