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Viewing all defined variables [duplicate]
...ython shell. What I want to have is Matlab style listout where you can see all the variables that have been defined up to a point (so I know which names I've used, their values and such).
...
Generating random numbers in Objective-C
...te the S-Boxes via
arc4random_addrandom().
There is no need to call arc4random_stir() before using arc4random(), since arc4random() automatically
initializes itself.
EXAMPLES
The following produces a drop-in replacement for the traditional rand() and random() functions using
...
How should I structure a Python package that contains Cython code
...od relies on the fact that building a .pyx file with Cython.Distutils.build_ext (at least with Cython version 0.14) always seems to create a .c file in the same directory as the source .pyx file.
Here is a cut-down version of setup.py which I hope shows the essentials:
from distutils.core import s...
Is there a standard sign function (signum, sgn) in C/C++?
...T val) {
return (T(0) < val) - (val < T(0));
}
Benefits:
Actually implements signum (-1, 0, or 1). Implementations here using copysign only return -1 or 1, which is not signum. Also, some implementations here are returning a float (or T) rather than an int, which seems wasteful.
Works ...
What is the native keyword in Java for?
...tation doesn’t have to use JNI. Certain JRE methods are handled intrinsically by the JVM. In fact, it’s not even mandatory that the implementation is actually native code. It’s just “implemented in a language other than the Java programming language”.
– Holger
...
e.printStackTrace equivalent in python
...
import traceback
traceback.print_exc()
When doing this inside an except ...: block it will automatically use the current exception. See http://docs.python.org/library/traceback.html for more information.
...
How to check if a table exists in a given schema
... (like OIDs) gets lost in translation from the system catalogs - which actually carry all information.
System catalogs
Your question was:
How to check whether a table exists?
SELECT EXISTS (
SELECT FROM pg_catalog.pg_class c
JOIN pg_catalog.pg_namespace n ON n.oid = c.relnamespace
WHE...
Equals(=) vs. LIKE
...tify an example where these operators produce obviously different results. Allow me to quote from the MySQL manual:
Per the SQL standard, LIKE performs matching on a per-character basis, thus it can produce results different from the = comparison operator:
mysql> SELECT 'ä' LIKE 'ae' COLLA...
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
...
Python error “ImportError: No module named”
Python is installed in a local directory.
28 Answers
28
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