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@property retain, assign, copy, nonatomic in Objective-C
..." is the default. Always use "nonatomic". I don't know why, but the book I read said there is "rarely a reason" to use "atomic". (BTW: The book I read is the BNR "iOS Programming" book.)
readwrite vs. readonly
- "readwrite" is the default. When you @synthesize, both a getter and a setter will be cr...
How to execute file I'm editing in Vi(m)
... it allows launching sequence of commands that are connected with pipe and read stdout.
For example:
! node %
is equivalent to opening command prompt window and launching commands:
cd my_current_directory
node my_current_file
See "Vim tips: Working with external commands" for details.
...
Understanding typedefs for function pointers in C
I have always been a bit stumped when I read other peoples' code which had typedefs for pointers to functions with arguments. I recall that it took me a while to get around to such a definition while trying to understand a numerical algorithm written in C a while ago. So, could you share your tips a...
setup.py examples?
...
READ THIS FIRST https://packaging.python.org/en/latest/current.html
Installation Tool Recommendations
Use pip to install Python packages
from PyPI.
Use virtualenv, or pyvenv to isolate application specific d...
How do I convert dates in a Pandas data frame to a 'date' data type?
...iles, in which case you can simply convert the date during the initial CSV read:
dfcsv = pd.read_csv('xyz.csv', parse_dates=[0]) where the 0 refers to the column the date is in.
You could also add , index_col=0 in there if you want the date to be your index.
See https://pandas.pydata.org/pandas-do...
Join vs. sub-query
...han LEFT [OUTER] JOIN, but in my opinion their strength is slightly higher readability.
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How to replace NaN values by Zeroes in a column of a Pandas Dataframe?
...te(df.loc[idx[:,mask_1],idx[[mask_2],:]].fillna(value=0))
It's one line, reads reasonably well (sort of) and eliminates any unnecessary messing with intermediate variables or loops while allowing you to apply fillna to any multi-level slice you like!
If anybody can find places this doesn't work p...
Tags for Emacs: Relationship between etags, ebrowse, cscope, GNU Global and exuberant ctags
...n C++ projects, and I went through Alex Ott's guide to CEDET and other threads about tags in StackOverflow, but I am still confused about how Emacs interfaces with these different tag systems to facilitate autocompletion, the looking up of definitions, navigation of source code base or the preview...
How can I remove an element from a list?
...he back of the list to the front.
A response to that post later in the thread states:
For deleting an element of a list, see R FAQ 7.1
And the relevant section of the R FAQ says:
... Do not set x[i] or x[[i]] to NULL, because this will remove the corresponding component from the list.
...
How to think in data stores instead of databases?
...Just layout your web page. Lay them all out. Now look at them. You're already 2/3 there.
If you forget the notion that database size matters and data shouldn't be duplicated then you're 3/4 there and you didn't even have to write any code! Let your views dictate your Models. You don't have t...