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Relative paths in Python
I'm building a simple helper script for work that will copy a couple of template files in our code base to the current directory. I don't, however, have the absolute path to the directory where the templates are stored. I do have a relative path from the script but when I call the script it treats t...
Python - Create a list with initial capacity
...
def doAppend( size=10000 ):
result = []
for i in range(size):
message= "some unique object %d" % ( i, )
result.append(message)
return result
def doAllocate( size=10000 ):
result=size*[None]
for i in range(size):
message= "some u...
warning about too many open figures
...ith all its axes, but leaves the window opened, such that it may be reused for other plots.
plt.close() closes a window, which will be the current window, if not specified otherwise. plt.close('all') will close all open figures.
The reason that del fig does not work is that the pyplot state-machin...
List directory tree structure in python?
...
Here's a function to do that with formatting:
import os
def list_files(startpath):
for root, dirs, files in os.walk(startpath):
level = root.replace(startpath, '').count(os.sep)
indent = ' ' * 4 * (level)
print('{}{}/'.format(ind...
Check if something is (not) in a list in Python
...on the container type that could be less efficient, or even incorrect. See for example bloom filters.
– orlp
May 2 '12 at 0:24
15
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What's the difference between echo, print, and print_r in PHP?
...an array or an object). print_r prints a variable in a more human-readable form: strings are not quoted, type information is omitted, array sizes aren't given, etc.
var_dump is usually more useful than print_r when debugging, in my experience. It's particularly useful when you don't know exactly wh...
What is the documents directory (NSDocumentDirectory)?
...ans that it can only access files and directories within its own contents. For example Documents and Library.
See the iOS Application Programming Guide.
To access the Documents directory of your applications sandbox, you can use the following:
iOS 8 and newer, this is the recommended method
+ (N...
Why does GCC generate 15-20% faster code if I optimize for size instead of speed?
...chines) have the tendency to generate noticeably faster code if I optimize for size ( -Os ) instead of speed ( -O2 or -O3 ), and I have been wondering ever since why.
...
Is there an expression for an infinite generator?
Is there a straight-forward generator expression that can yield infinite elements?
7 Answers
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Convert Django Model object to dict with all of the fields intact
...ango Model object to a dict with all of its fields? All ideally includes foreign keys and fields with editable=False .
1...