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Assign pandas dataframe column dtypes
I want to set the dtype s of multiple columns in pd.Dataframe (I have a file that I've had to manually parse into a list of lists, as the file was not amenable for pd.read_csv )
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Get size of all tables in database
I have inherited a fairly large SQL Server database. It seems to take up more space than I would expect, given the data it contains.
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View's getWidth() and getHeight() returns 0
...reating all of the elements in my android project dynamically. I am trying to get the width and height of a button so that I can rotate that button around. I am just trying to learn how to work with the android language. However, it returns 0.
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How do I correctly clean up a Python object?
...d recommend using Python's with statement for managing resources that need to be cleaned up. The problem with using an explicit close() statement is that you have to worry about people forgetting to call it at all or forgetting to place it in a finally block to prevent a resource leak when an excep...
How to handle Back button with in the dialog?
I am developing an application that when the button is pressed, it opens a dialog with OK and Cancel buttons.
8 Answers
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Assign null to a SqlParameter
The following code gives an error - "No implicit conversion from DBnull to int."
18 Answers
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What's the difference between lapply and do.call?
...by two function: lapply and do.call . It seems that they're just similar to map function in Lisp. But why are there two functions with such a different name? Why doesn't R just use a function called map ?
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JavaScript: What are .extend and .prototype used for?
I am relatively new to JavaScript and keep seeing .extend and .prototype in third party libraries I am using. I thought it had to do with the Prototype javascript library, but I am beginning to think that is not the case. What are these used for?
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Any way to limit border length?
Is there any way to limit the length of a border. I have a <div> that has a bottom border, but I want to add a border on the left of the <div> that only stretches half of the way up.
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How to add an extra column to a NumPy array
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I think a more straightforward solution and faster to boot is to do the following:
import numpy as np
N = 10
a = np.random.rand(N,N)
b = np.zeros((N,N+1))
b[:,:-1] = a
And timings:
In [23]: N = 10
In [24]: a = np.random.rand(N,N)
In [25]: %timeit b = np.hstack((a,np.zer...