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How to use PyCharm to debug Scrapy projects
... so accept spider name as an argument of your run config. Then import sys spider = sys.argv[1] cmdline.execute("scrapy crawl {}".format(spider).split())
– miguelfg
Oct 1 '17 at 20:47
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How can I convert a datetime object to milliseconds since epoch (unix time) in Python?
I have a Python datetime object that I want to convert to unix time, or seconds/milliseconds since the 1970 epoch.
13 Ans...
Is unsigned integer subtraction defined behavior?
...he result of the addition is unsigned int. Then that result is implicitly converted to the type required in context, a conversion which fails because the value is not representable in the new type.
– Ben Voigt
Oct 14 '15 at 3:20
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Why do Python's math.ceil() and math.floor() operations return floats instead of integers?
...vident in your comment:
The whole point of ceil/floor operations is to convert floats to integers!
The point of the ceil and floor operations is to round floating-point data to integral values. Not to do a type conversion. Users who need to get integer values can do an explicit conversion fo...
Sort a single String in Java
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No there is no built-in String method. You can convert it to a char array, sort it using Arrays.sort and convert that back into a String.
String test= "edcba";
char[] ar = test.toCharArray();
Arrays.sort(ar);
String sorted = String.valueOf(ar);
Or, when you want to dea...
import module from string variable
... globals()[module] = module_obj
except ImportError:
sys.stderr.write("ERROR: missing python module: " + module + "\n")
sys.exit(1)
and yes, for python 2.7> you have other options - but for 2.6<, this works.
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Difference between java.util.Random and java.security.SecureRandom
....util.Random source code (JDK 7u2), from a comment on the method protected int next(int bits), which is the one that generates the random values:
This is a linear congruential pseudorandom number generator, as
defined by D. H. Lehmer and described by Donald E. Knuth in
The Art of Compute...
Why is list initialization (using curly braces) better than the alternatives?
...on does not allow narrowing (§iso.8.5.4). That is:
An integer cannot be converted to another integer that cannot hold its value. For example, char
to int is allowed, but not int to char.
A floating-point value cannot be converted to another floating-point type that cannot hold its
value. For exam...
How to organize large R programs?
... different functionality in their own files.
But I don't like R's package system. It's rather hard to use.
I prefer a lightweight alternative, to place a file's functions inside an environment (what every other language calls a "namespace") and attach it. For example, I made a 'util' group of fu...
Java: How to convert List to Map
... have conversation with a colleague about what would be the optimal way to convert List to Map in Java and if there any specific benefits of doing so.
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