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Fastest way to determine if an integer's square root is an integer
... CPU (x86) and programming language (C/C++). Your results may vary, especially because I don't know how the Java factor will play out.
My approach is threefold:
First, filter out obvious answers. This includes negative numbers and looking at the last 4 bits. (I found looking at the last six di...
Why does pylint object to single character variable names?
...s and using pylint to make my code more pythonic, but I'm puzzled by the fact that pylint doesn't like single character variable names. I have a few loops like this:
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`static` keyword inside function?
...e value of the given variable ($has_run in your example) between multiple calls.
You could use this for different purposes, for example:
function doStuff() {
static $cache = null;
if ($cache === null) {
$cache = '%heavy database stuff or something%';
}
// code using $cache
}
In th...
Reading a binary file with python
I find particularly difficult reading binary file with Python. Can you give me a hand?
I need to read this file, which in Fortran 90 is easily read by
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What do the python file extensions, .pyc .pyd .pyo stand for?
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.py: This is normally the input source code that you've written.
.pyc: This is the compiled bytecode. If you import a module, python will build a *.pyc file that contains the bytecode to make importing it again later easier (and faster).
.pyo...
How to set layout_weight attribute dynamically from code?
...t the value for the attribute layout_weight for button in android dynamically from java code ?
9 Answers
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Select by partial string from a pandas DataFrame
...egex search is not required, so specify regex=False to disable it.
#select all rows containing "foo"
df1[df1['col'].str.contains('foo', regex=False)]
# same as df1[df1['col'].str.contains('foo')] but faster.
col
0 foo
1 foobar
Performance wise, regex search is slower than substring s...
How to change height of grouped UITableView header?
I know how to change the height of the section headers in the table view. But I am unable to find any solution to change the default spacing before the first section.
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How to ignore xargs commands if stdin input is empty?
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For GNU xargs, you can use the -r or --no-run-if-empty option:
--no-run-if-empty
-r If the standard input does not contain any nonblanks, do not run the command. Normally, the command is run once even if th...
Python Pandas: Get index of rows which column matches certain value
... frame (whose data may be gibabytes). What about dftest? Doesn't this also allocate a very large intermediate object where the returned index may be very small, or even empty. Are these magically optimized away using lazy views. If not then surely there must be an efficient way.
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