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How do I get the row count of a pandas DataFrame?
...g",
setup=lambda n: pd.DataFrame(np.arange(n * 3).reshape(n, 3)),
n_range=[2**k for k in range(25)],
kernels=[
lambda data: data.shape[0],
lambda data: data[0].count(),
lambda data: len(data.index),
],
labels=["data.shape[0]", "data[0].count()", "len(data....
How to get one value at a time from a generator function in Python?
...en by subclassing. In Python 3, however, this function has been renamed to __next__(), to be consistent with other special functions.
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Conditional import of modules in Python
...ad of relying on the user; here's pySerial doing it as an example.
serial/__init__.py
import sys
if sys.platform == 'cli':
from serial.serialcli import Serial
else:
import os
# chose an implementation, depending on os
if os.name == 'nt': # sys.platform == 'win32':
from se...
Can I use git diff on untracked files?
...es by simply supplying the path to both files.
git diff --no-index tracked_file untracked_file
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How to convert Java String into byte[]?
...(Charset.forName("UTF-8"));
byte[] b = string.getBytes(StandardCharsets.UTF_8); // Java 7+ only
However the problem you appear to be wrestling with is that this doesn't display very well. Calling toString() will just give you the default Object.toString() which is the class name + memory address...
How to post data in PHP using file_get_contents?
I'm using PHP's function file_get_contents() to fetch contents of a URL and then I process headers through the variable $http_response_header .
...
Why does changing the returned variable in a finally block not change the return value?
...iable
5: getstatic #8; //loading "dev" from a static variable
8: astore_0 //storing "dev" to a temp variable
9: ldc #9; //loading String "override variable s"
11: putstatic #8; //setting a static variable
14: aload_0 //loading a temp avariable
15: areturn //retu...
How do I time a method's execution in Java?
...one place.
Date
Date startDate = Calendar.getInstance().getTime();
long d_StartTime = new Date().getTime();
Thread.sleep(1000 * 4);
Date endDate = Calendar.getInstance().getTime();
long d_endTime = new Date().getTime();
System.out.format("StartDate : %s, EndDate : %s \n", startDate, endDate);
Syst...
OnCreateOptionsMenu() not called in Fragment
...cannot be cast to android.widget.SearchView
– Android_programmer_office
Nov 26 '13 at 20:26
...
Simple Digit Recognition OCR in OpenCV-Python
...e KNearest for simple OCR purposes).
1) My first question was about letter_recognition.data file that comes with OpenCV samples. I wanted to know what is inside that file.
It contains a letter, along with 16 features of that letter.
And this SOF helped me to find it. These 16 features are explain...