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what is the most efficient way of counting occurrences in pandas?
...counts() should serve. By skipping the groupby machinery, you'll save some time. I'm not sure why count should be much slower than max. Both take some time to avoid missing values. (Compare with size.)
In any case, value_counts has been specifically optimized to handle object type, like your words,...
How to use the same C++ code for Android and iOS?
...tual Machine. So the only way to access C++ code is using JNI, please take time to read the basics of JNI. Fortunately, today's Android Studio IDE has vast improvements on JNI side, and a lot of problems are shown to you while you edit your code.
The code by steps
Our sample is a simple app that y...
Difference between Bridge pattern and Adapter pattern
...ned the stub, narrowed it down and called it "pseudo-remotely". This often times caused performance problems (esp. when really called over the wire). Experienced developers would use the facade pattern to provide a very coarse-grained interface to the client. This facade would then in turn do multip...
Options for HTML scraping? [closed]
...e part of the standard Python library. These work by calling methods every time you enter/exit a tag and encounter html text. They're like Expat if you're familiar with that. These libraries are especially useful if you are going to parse very large files and creating a DOM tree would be long and ex...
Postgres and Indexes on Foreign Keys and Primary Keys
... @Matthias - Ah, got it. Thanks. Yeah, I obviously didn't take time to read through the code. It wasn't critical enough to bother. The OP could've mentioned the limitations. Maybe I'll check it out again sometime.
– juanitogan
Mar 31 '17 at 1:23
...
How to insert element into arrays at specific position?
... $size = count($array); //because I am going to use this more than one time
if (!is_int($index) || $index < 0 || $index > $size)
{
return -1;
}
else
{
$temp = array_slice($array, 0, $index);
$temp[] = $val;
re...
add a string prefix to each value in a string column using Pandas
...r's solution (python 3.6.4):
df = pd.DataFrame({'col':['a', 0]*200000})
%timeit df['col'].apply(lambda x: f"str{x}")
117 ms ± 451 µs per loop (mean ± std. dev. of 7 runs, 10 loops each)
%timeit 'str' + df['col'].astype(str)
112 ms ± 1.04 ms per loop (mean ± std. dev. of 7 runs, 10 loops each...
How do CUDA blocks/warps/threads map onto CUDA cores?
...m different warps.
3'. A GTX560 can have 8 SM * 8 blocks = 64 blocks at a time or 8 SM * 48 warps = 512 warps if the kernel does not max out registers or shared memory. At any given time on a portion of the work will be active on SMs. Each SM has multiple execution units (more than CUDA cores). Whi...
Android EditText delete(backspace) key event
How can I detect delete (backspace) key event for a editText? I've tried using TextWatcher, but when the editText is empty, when I press delete key, nothing happens. I want to detect delete key press foe an editText even if it has no text.
...
Execution of Python code with -m option or not
...ain code that is invoked on their execution as a script. An example is the timeit module:
Some python code is intended to be run as a module: (I think this example is better than the commandline option doc example)
$ python -m timeit '"-".join(str(n) for n in range(100))'
10000 loops, best of 3: ...