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How can I wait for a thread to finish with .NET?
I've never really used threading before in C# where I need to have two threads, as well as the main UI thread. Basically, I have the following.
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How to make good reproducible pandas examples
...s.
Disclaimer: Writing a good question is HARD.
The Good:
do include small* example DataFrame, either as runnable code:
In [1]: df = pd.DataFrame([[1, 2], [1, 3], [4, 6]], columns=['A', 'B'])
or make it "copy and pasteable" using pd.read_clipboard(sep='\s\s+'), you can format the text for Sta...
Get Image size WITHOUT loading image into memory
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As the comments allude, PIL does not load the image into memory when calling .open. Looking at the docs of PIL 1.1.7, the docstring for .open says:
def open(fp, mode="r"):
"Open an image file, without loading the raster data"
There ar...
How do I provide custom cast support for my class?
...ou want users to have to cast it or whether you want it to happen automagically. Generally, one direction will always work, that's where you use implicit, and the other direction can sometimes fail, that's where you use explicit.
The syntax is like this:
public static implicit operator dbInt64(Byt...
sizeof single struct member in C
... char text[member_size(Parent, text)];
int used;
} Child;
I'm actually a bit surprised that sizeof((type *)0)->member) is even allowed as a constant expression. Cool stuff.
share
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impr...
Installing python module within code
I need to install a package from PyPi straight within my script.
Maybe there's some module or distutils ( distribute , pip etc.) feature which allows me to just execute something like pypi.install('requests') and requests will be installed into my virtualenv.
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How does BLAS get such extreme performance?
...e optimization. This boost significantly exceeds the second boost from parallelism and other hardware optimizations.
By the way, most (or even all) of the high performance BLAS implementations are NOT implemented in Fortran. ATLAS is implemented in C. GotoBLAS/OpenBLAS is implemented in C and i...
Which SQL query is faster? Filter on Join criteria or Where clause?
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Performance-wise, they are the same (and produce the same plans)
Logically, you should make the operation that still has sense if you replace INNER JOIN with a LEFT JOIN.
In your very case this will look like this:
SELECT *
FROM TableA a
LEFT JOIN
TableXRef x
ON x.TableAID = ...
Python extract pattern matches
...h a standard python REPL, the last result is stored in a special variable called _. It isn't valid outside anywhere else.
– UltraInstinct
Mar 13 '19 at 2:25
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Installing older version of R package
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To install an older version of a package from source (within R):
packageurl <- "http://cran.r-project.org/src/contrib/Archive/ggplot2/ggplot2_0.9.1.tar.gz"
install.packages(packageurl, repos=NULL, type="source")
If this doesn'...