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Are PHP Variables passed by value or by reference?
... function is changed, it does not get changed outside of the function). To allow a function to modify its arguments, they must be passed by reference.
To have an argument to a function always passed by reference, prepend an ampersand (&) to the argument name in the function definition.
&l...
How to replace NaN values by Zeroes in a column of a Pandas Dataframe?
...olumn, select just that column. in this case I'm using inplace=True to actually change the contents of df.
In [12]: df[1].fillna(0, inplace=True)
Out[12]:
0 0.000000
1 0.570994
2 0.000000
3 -0.229738
4 0.000000
Name: 1
In [13]: df
Out[13]:
0 1
0 NaN 0.0000...
How to normalize a path in PowerShell?
...WINDOWS\system32\fred\frog\..\frag
With an absolute base, it is safe to call the .NET API GetFullPath:
[System.IO.Path]::GetFullPath((Join-Path (Join-Path (pwd) fred\frog) '..\frag'))
Which gives you the fully qualified path and with the .. removed:
C:\WINDOWS\system32\fred\frag
It's not com...
Oracle SQL: Update a table with data from another table
...
This is called a correlated update
UPDATE table1 t1
SET (name, desc) = (SELECT t2.name, t2.desc
FROM table2 t2
WHERE t1.id = t2.id)
WHERE EXISTS (
SELECT 1
FROM table2 t2...
How do I expand the output display to see more columns of a pandas DataFrame?
...: None] [currently: None]
: float or None
if set to a float value, all float values smaller then the given threshold
will be displayed as exactly 0 by repr and friends.
display.colheader_justify: [default: right] [currently: right]
: 'left'/'right'
Controls the justification ...
Will Emacs make me a better programmer? [closed]
... who are merely good or competent will pick up an IDE and get to know it really well, and maybe do decently enough in it, but they'll restrict themselves to what the IDE provides for them. In other words, they adapt themselves to the IDE. The great programmers, on the other hand, will adapt their en...
Download JSON object as a file from browser
...or without explicit clicking since I want to trigger the download automatically at some point from js.
JS solution (no HTML required):
function downloadObjectAsJson(exportObj, exportName){
var dataStr = "data:text/json;charset=utf-8," + encodeURIComponent(JSON.stringify(exportObj));
var ...
Comparing two dataframes and getting the differences
...df2, works only for dataframes with identical rows and columns. In fact, all dataframes axes are compared with _indexed_same method, and exception is raised if differences found, even in columns/indices order.
If I got you right, you want not to find changes, but symmetric difference. For that, o...
Python Empty Generator Function
... list(f())
[None]
Why not just use iter(())?
This question asks specifically about an empty generator function. For that reason, I take it to be a question about the internal consistency of Python's syntax, rather than a question about the best way to create an empty iterator in general.
If ques...
Should I store entire objects, or pointers to objects in containers?
... storing pointers into vector can be efficient if used along with a custom allocator for the pointees. The custom allocator has to take care of the cache locality, for example using placement new (see en.wikipedia.org/wiki/Placement_syntax#Custom_allocators).
– amit
...