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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...
What is a callback function?
...ant is to be able to call factorial in the following way:
factorial(really_big_number, what_to_do_with_the_result)
The second parameter, what_to_do_with_the_result, is a function you send along to factorial, in the hope that factorial will call it on its result before returning.
Yes, this means...
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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SVN Error - Not a working copy
...ch worked for the OP) didn't fix it. Here's what I did:
$ mv papers papers_
$ svn cleanup
$ svn revert papers
Reverted 'papers'
$ mv papers_/ papers
$ svn add papers
That worked.
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Reload an iframe with jQuery
...
This Jquery worked like a charm for me: $('#map_iframe').attr('src', $('#map_iframe').attr('src'));
– Topher Hunt
Jul 1 '14 at 19:00
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...
端侧AI（OnDeviceAI）使用指导 · App Inventor 2 中文网
...，将同名事件的处理合并到一个事件积木中。
when 按钮_加载.Click() {
OnDeviceAI1.LoadModel("model.ms")
}
when OnDeviceAI1.ModelLoaded(输入信息JSON) {
标签1.Text = 输入信息JSON
}
when OnDeviceAI1.Error(错误信息) {
标签1.Text = 错误信息
}
案...
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...