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Random hash in Python
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+1 for not computing a relatively expensive hash from a random number: this approach is 5x faster.
– Nicolas Dumazet
Jun 11 '09 at 1:36
11
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How do I check OS with a preprocessor directive?
...them, with links to where they're found:
Windows
_WIN32 Both 32 bit and 64 bit
_WIN64 64 bit only
Unix (Linux, *BSD, Mac OS X)
See this related question on some of the pitfalls of using this check.
unix
__unix
__unix__
Mac OS X
__APPLE__
__MACH__
Both are defined; checking for eith...
RE error: illegal byte sequence on Mac OS X
...s on demand:
Standard utility iconv can be used to convert to (-t) and/or from (-f) encodings; iconv -l lists all supported ones.
Examples:
Convert FROM ISO-8859-1 to the encoding in effect in the shell (based on LC_CTYPE, which is UTF-8-based by default), building on the above example:
# Conv...
Storing time-series data, relational or non?
...evation.
Correction
It is not "filtering out the un-needed data"; it is selecting only the needed data. Yes, of course, if you have an Index to support the columns identified in the WHERE clause, it is very fast, and the query does not depend on the size of the table (grabbing 1,000 rows from a ...
Git ignore file for Xcode projects
...bout this, but in practice it seems you should ignore it.
# - minor tweaks from Jona and Coeur (slightly more precise xc* filtering/names)
# 2014 updates:
# - appended non-standard items DISABLED by default (uncomment if you use those tools)
# - removed the edit that an SO.com moderator made without...
Access restriction on class due to restriction on required library rt.jar?
...ings in the project properties.
Remove the JRE System Library
Add it back; Select "Add Library" and select the JRE System Library. The default worked for me.
This works because you have multiple classes in different jar files. Removing and re-adding the JRE lib will make the right classes be first...
Android static object lifecycle
...vity
state so that on restart, the fields
get filled with their previously
selected values, you can implement
the onSaveInstanceState() activity
method - note that this is not
recommended for between activities
persistance of states.
You can get some code examples of the usage of preferences, inte...
Regular expressions in an Objective-C Cocoa application
...Objective-C? Could you maybe include a code snippet for converting to and from NSString? thanks again!
– dreeves
Jan 7 '09 at 21:45
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What REALLY happens when you don't free after malloc?
...ce is explicitly deallocated). The lifetime of an allocated object extends
from the allocation until the deallocation.[...]
So it has not to be given that the environment is doing the freeing job for you.
Otherwise it would be added to the last sentence: "Or until the program terminates."
So in oth...
Changing the current working directory in Java?
How can I change the current working directory from within a Java program? Everything I've been able to find about the issue claims that you simply can't do it, but I can't believe that that's really the case.
...