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How to import data from mongodb to pandas?
... else:
conn = MongoClient(host, port)
return conn[db]
def read_mongo(db, collection, query={}, host='localhost', port=27017, username=None, password=None, no_id=True):
""" Read from Mongo and Store into DataFrame """
# Connect to MongoDB
db = _connect_mongo(host=host, p...
Why doesn't C# support the return of references?
I have read that .NET supports return of references, but C# doesn't. Is there a special reason? Why I can't do something like:
...
What's the best way to share data between activities?
...tages: you can launch the activity from other places and, if the data is already persisted, it should work just fine.
Disadvantages: it’s cumbersome and takes more time to implement. Requires more code and thus more chance of introducing bugs. It will also be much slower.
Some of the ways to per...
Android splash screen image sizes to fit all devices
...40x960
large (hdpi): 480x800
medium (mdpi): 320x480
small (ldpi): 240x320
Read 9-patch image introduction in Android Developer Guide
Design images that have areas that can be safely stretched without compromising the end result
With this, Android will select the appropriate file for the device's ...
How to get different colored lines for different plots in a single figure?
... x)
plt.plot(x, 3 * x)
plt.plot(x, 4 * x)
plt.show()
And, as you may already know, you can easily add a legend:
import matplotlib.pyplot as plt
import numpy as np
x = np.arange(10)
plt.plot(x, x)
plt.plot(x, 2 * x)
plt.plot(x, 3 * x)
plt.plot(x, 4 * x)
plt.legend(['y = x', 'y = 2x', 'y = 3x'...
Setting PayPal return URL and making it auto return?
...$req variable and add CMD key value pair
$req = 'cmd=_notify-validate';
// Read the post from PayPal
foreach ($_POST as $key => $value) {
$value = urlencode(stripslashes($value));
$req .= "&$key=$value";
}
// Now Post all of that back to PayPal's server using curl, and validate everyt...
What is a “callback” in C and how are they implemented?
From the reading that I have done, Core Audio relies heavily on callbacks (and C++, but that's another story).
9 Answers
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What are the differences between a pointer variable and a reference variable in C++?
I know references are syntactic sugar, so code is easier to read and write.
41 Answers
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What is (functional) reactive programming?
I've read the Wikipedia article on reactive programming . I've also read the small article on functional reactive programming . The descriptions are quite abstract.
...
How to write very long string that conforms with PEP8 and prevent E501
...ng of your example.
Personally I don't like the backslashes, and I recall reading somewhere that its use is actually deprecated in favor of this form which is more explicit. Remember "Explicit is better than implicit."
I consider the backslash to be less clear and less useful because this is actua...