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MongoDB Aggregation: How to get total records count?
...sults simultaneously in single query. I can't explain how I felt when I finally achieved it LOL.
$result = $collection->aggregate(array(
array('$match' => $document),
array('$group' => array('_id' => '$book_id', 'date' => array('$max' => '$book_viewed'), 'views' => array('...
Two submit buttons in one form
...
Normally, all inputs in the form are sent with the form. Since a button's value is submitted only if clicked, you'd have to search the form values for these pre-defined names. I think the other answer (stackoverflow.com/a/21778...
How to create a density plot in matplotlib?
...with R. This is because gaussian_kde tries to infer the bandwidth automatically. You can play with the bandwidth in a way by changing the function covariance_factor of the gaussian_kde class. First, here is what you get without changing that function:
However, if I use the following code:
import...
AfxGetMainWnd函数解惑 - C/C++ - 清泛网 - 专注C/C++及内核技术
...时也会失灵。不信， 你测试一下下面的代码：
unsigned __stdcall SecondThreadFunc( void* pArguments )
{
CMainFrame* pMainWnd = (CMainFrame*)AfxGetMainWnd();
if (NULL!=pMainWnd)
{
CView *pView = pMainWnd->GetActiveView();
if (NULL...
How to select all instances of a variable and edit variable name in Sublime
If I select a variable (not just any string) in my code, all other instances of that variable get a stroke (white outline) around them:
...
serve current directory from command line
...also running on a Mac. Tried it with Ruby 1.8.7, 1.9.3 and 2.0.0, and they all work. Weird.
– Daniel Perez Alvarez
Sep 9 '13 at 9:04
7
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Do sealed classes really offer performance Benefits?
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The JITter will sometimes use non-virtual calls to methods in sealed classes since there is no way they can be extended further.
There are complex rules regarding calling type, virtual/nonvirtual, and I don't know them all so I can't really outline them for you, but ...
Lazy Method for Reading Big File in Python?
...
To write a lazy function, just use yield:
def read_in_chunks(file_object, chunk_size=1024):
"""Lazy function (generator) to read a file piece by piece.
Default chunk size: 1k."""
while True:
data = file_object.read(chunk_size)
if not data:
...
How to get method parameter names?
...ious code object properties for you.
>>> inspect.getfullargspec(a_method)
(['arg1', 'arg2'], None, None, None)
The other results are the name of the *args and **kwargs variables, and the defaults provided. ie.
>>> def foo(a, b, c=4, *arglist, **keywords): pass
>>> ins...
Can (domain name) subdomains have an underscore “_” in it?
...interior characters only letters, digits, and hyphen." Which part of that allows an underscore?
– claudekennilol
Sep 16 '16 at 19:01
2
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