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How do I perform the SQL Join equivalent in MongoDB?
...ttps://docs.mongodb.org/master/reference/operator/aggregation/lookup/#pipe._S_lookup
From the docs:
{
$lookup:
{
from: <collection to join>,
localField: <field from the input documents>,
foreignField: <field from the documents of the "from" collection>...
Reimport a module in python while interactive
...from the importlib library instead:
import importlib
importlib.reload(some_module)
If you are using python 3.2 or 3.3 you should:
import imp
imp.reload(module)
instead. See http://docs.python.org/3.0/library/imp.html#imp.reload
If you are using ipython, definitely consider using the autor...
How to import multiple .csv files at once?
...olutions in other answers using things like do.call(rbind,...), dplyr::bind_rows() or data.table::rbindlist().
If you really want each data frame in a separate object, even though that's often inadvisable, you could do the following with assign:
temp = list.files(pattern="*.csv")
for (i in 1:lengt...
How to detect reliably Mac OS X, iOS, Linux, Windows in C preprocessor? [duplicate]
... be found here.
Here is an example for gcc:
#if defined(WIN32) || defined(_WIN32) || defined(__WIN32__) || defined(__NT__)
//define something for Windows (32-bit and 64-bit, this part is common)
#ifdef _WIN64
//define something for Windows (64-bit only)
#else
//define something...
How to find list intersection?
...
Make a set out of the larger one:
_auxset = set(a)
Then,
c = [x for x in b if x in _auxset]
will do what you want (preserving b's ordering, not a's -- can't necessarily preserve both) and do it fast. (Using if x in a as the condition in the list compreh...
Is cout synchronized/thread-safe?
... @ildjarn - No, @edA-qa mort-ora-y is correct. As long as cout.sync_with_stdio() is true, using cout to output characters from multiple threads without additional synchronization is well-defined, but only on the level of individual bytes. Thus, cout << "ab"; and cout << "cd" exec...
How to terminate a Python script
...stedmatrix below points out that if you want a 'hard exit', you can use os._exit(*errorcode*), though it's likely os-specific to some extent (it might not take an errorcode under windows, for example), and it definitely is less friendly since it doesn't let the interpreter do any cleanup before the ...
undefined reference to `__android_log_print'
...
Try the following in your Android.mk file:
LOCAL_LDLIBS := -L$(SYSROOT)/usr/lib -llog
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GraphViz - How to connect subgraphs?
...luster, that can be linked to even if the cluster is empty otherwise. DUMMY_0 [shape=point style=invis]
– DevSolar
Jun 25 '12 at 7:36
2
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android: move a view on touch move (ACTION_MOVE)
...ss MyActivity extends Activity implements View.OnTouchListener {
TextView _view;
ViewGroup _root;
private int _xDelta;
private int _yDelta;
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
_root = (ViewGroup...