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How to write a multidimensional array to a text file?
...is specified by the comments kwarg). (This looks more verbose than it actually is...)
import numpy as np
# Generate some test data
data = np.arange(200).reshape((4,5,10))
# Write the array to disk
with open('test.txt', 'w') as outfile:
# I'm writing a header here just for the sake of readabil...
Multiple Updates in MySQL
...has new records then i will end up inserting only the ids and count except all other information. if and only if there is an entry for the id then it should update else it should skip. what shall i do?
– Jayapal Chandran
Aug 30 '10 at 13:30
...
How to know if an object has an attribute in Python
...n is that, if the property is likely to be there most of the time, simply call it and either let the exception propagate, or trap it with a try/except block. This will likely be faster than hasattr. If the property is likely to not be there most of the time, or you're not sure, using hasattr will pr...
How to escape single quotes within single quoted strings
...
If you really want to use single quotes in the outermost layer, remember that you can glue both kinds of quotation. Example:
alias rxvt='urxvt -fg '"'"'#111111'"'"' -bg '"'"'#111111'"'"
# ^^^^^ ^^^^^ ^...
Python: try statement in a single line
...ther dynamic languages. The safer way (and the prevailing style) is to set all variables to something. If they might not get set, set them to None first (or 0 or '' or something if it is more applicable.)
If you do assign all the names you are interested in first, you do have options.
The best...
What does the exclamation mark mean in a Haskell declaration?
...
It's a strictness declaration. Basically, it means that it must be evaluated to what's called "weak head normal form" when the data structure value is created. Let's look at an example, so that we can see just what this means:
data Foo = Foo Int Int !Int !(May...
Why do some functions have underscores “__” before and after the function name?
...rms using leading or trailing underscores are
recognized (these can generally be combined with any case convention):
_single_leading_underscore: weak "internal use" indicator. E.g. from M import * does not import objects whose name starts with an underscore.
single_trailing_underscore_: ...
How to uninstall Python 2.7 on a Mac OS X 10.6.4?
... PATH variable by reverting my .bash_profile . But I also want to remove all directories, files, symlinks, and entries that got installed by the Python 2.7 install package. I've got the install package from http://www.python.org/ . What directories/files/configuration file entries do I need to re...
How can I force division to be floating point? Division keeps rounding down to 0?
... a floating point number in Python in the following?
c = a / b
What is really being asked here is:
"How do I force true division such that a / b will return a fraction?"
Upgrade to Python 3
In Python 3, to get true division, you simply do a / b.
>>> 1/2
0.5
Floor division, the classic di...
Does Go have “if x in” construct similar to Python?
...ion without separate methods for every single type
– Allen
May 13 '15 at 4:33
29
It could be done...