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Creating an empty Pandas DataFrame, then filling it?
...C': 'xyz'}, ignore_index=True)
df.dtypes
A object # yuck!
B float64
C object
dtype: object
Dealing with object columns is never a good thing, because pandas cannot vectorize operations on those columns. You will need to do this to fix it:
df.infer_objects().dtypes
A int64
B fl...
In Django - Model Inheritance - Does it allow you to override a parent model's attribute?
...he question. Indeed, only the LongNamedRestaurant model was created in database, Place was not.
A solution is to create an abstract model representing a "Place", eg. AbstractPlace, and inherit from it:
class AbstractPlace(models.Model):
name = models.CharField(max_length=20)
rating = model...
You must enable the openssl extension to download files via https
... Where is this line? In which file? the php.ini in 1, C:\wamp64\bin\apache OR 2. C:\wamp64\bin\php\php7.0.0 ?
– MyDaftQuestions
Apr 3 '16 at 14:54
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Call UrlHelper in models in ASP.NET MVC
...ty on a created MyModel object will return the valid Url to view the Model based on the routing in Global.asax
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Lambda function in list comprehensions
...(map(lambda x: x*x, range(10))) will give you [0, 1, 4, 9, 16, 25, 36, 49, 64, 81]
– rrlamichhane
Jun 12 at 22:58
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Getting key with maximum value in dictionary?
...50, 56: 20, 57: 33,
58: 20, 59: 33, 60: 20, 61: 20, 62: 108, 63: 108, 64: 7, 65: 28, 66: 28, 67: 28,
68: 15, 69: 15, 70: 15, 71: 103, 72: 23, 73: 116, 74: 23, 75: 15, 76: 23, 77: 23,
78: 36, 79: 36, 80: 10, 81: 23, 82: 111, 83: 111, 84: 10, 85: 10, 86: 31, 87: 31,
88: 18, 89: 31,...
Mapping two integers to one, in a unique and deterministic way
... * (A + B + 1) / 2 + A;
(-32768, -32768) => 8589803520 which is Int64. 64 bit output for 16 bit inputs may be so unpardonable!!
Szudzik's function:
A = a >= 0 ? 2 * a : -2 * a - 1;
B = b >= 0 ? 2 * b : -2 * b - 1;
A >= B ? A * A + A + B : A + B * B;
(-32768, -32768) => 4...
How do I keep track of pip-installed packages in an Anaconda (Conda) environment?
...
64
conda will only keep track of the packages it installed. And pip will give you the packages tha...
How to get unique device hardware id in Android? [duplicate]
...droid device ID?
More specifically, Settings.Secure.ANDROID_ID. This is a 64-bit quantity that is generated and stored when the device first boots. It is reset when the device is wiped.
ANDROID_ID seems a good choice for a unique device identifier. There are downsides: First, it is not 100% reliab...
How to loop through files matching wildcard in batch file
I have a set of base filenames, for each name 'f' there are exactly two files, 'f.in' and 'f.out'. I want to write a batch file (in Windows XP) which goes through all the filenames, for each one it should:
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