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Jinja2 template variable if None Object set a default value
...p.User['first_name'] if p != None else 'NONE' }}
or if you need an empty string:
{{ p.User['first_name'] if p != None }}
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Where can I learn how to write C code to speed up slow R functions? [closed]
...rikes me is that you find R somewhat tedious (data manipulation, graphics, string manipulatio, etc ...). Well get prepared for many more surprises with the internal C API of R. This is very tedious.
From time to time, I read the R-exts or R-ints manuals. This helps. But most of the time, when I re...
How to change the status bar color in Android?
...t of all it's not a duplicate as in How to change the background color of android status bar
19 Answers
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How to retrieve a module's path?
...(__file__) can also be tricky. At least on my system, it returns an empty string if you call it from the same directory as the file. ex.
# foo.py
import os
print '__file__ is:', __file__
print 'os.path.dirname(__file__) is:', os.path.dirname(__file__)
will output:
__file__ is: foo.py
os.path.d...
How to check for valid email address? [duplicate]
... re.fullmatch which is preferable to re.match.
Note the r in front of the string; this way, you won't need to escape things twice.
If you have a large number of regexes to check, it might be faster to compile the regex first:
import re
EMAIL_REGEX = re.compile(r"... regex here ...")
if not EMAI...
Commenting in a Bash script inside a multiline command
...omment here` \
def `#Another chance for a comment` \
xyz, etc.
And for pipelines specifically, there is a clean solution with no overhead:
echo abc | # Normal comment OK here
tr a-z A-Z | # Another normal comment OK here
sort | # The pipelines are automatically co...
Is it possible to make the -init method private in Objective-C?
...release" method of creating singletons. It's virtually always unnecessary and is just adding complication for no real significant advantage.
Instead, just write your code such that your +sharedWhatever method is how you access a singleton, and document that as the way to get the singleton instance...
How to get whole and decimal part of a number?
... not going to end up being represented in scientific notation when cast to string. If it's a really really huge or really really tiny number then this won't be the case and this method will break.
– GordonM
Oct 4 '15 at 9:37
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How to view files in binary from bash?
...
vi your_filename
hit esc
Type :%!xxd to view the hex strings, the n :%!xxd -r to return to normal editing.
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Docker how to change repository name or rename image?
... answered Aug 9 '14 at 0:50
AndyAndy
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