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Drop data frame columns by name
...DF) %in% drops)]
Or, alternatively, you can make a list of those to keep and refer to them by name :
keeps <- c("y", "a")
DF[keeps]
EDIT :
For those still not acquainted with the drop argument of the indexing function, if you want to keep one column as a data frame, you do:
keeps <- "y"
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C# switch on type [duplicate]
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I usually use a dictionary of types and delegates.
var @switch = new Dictionary<Type, Action> {
{ typeof(Type1), () => ... },
{ typeof(Type2), () => ... },
{ typeof(Type3), () => ... },
};
@switch[typeof(MyType)]();
It's a little ...
Can I draw rectangle in XML?
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Yes you can and here is one I made earlier:
<?xml version="1.0" encoding="UTF-8"?>
<shape xmlns:android="http://schemas.android.com/apk/res/android" android:id="@+id/listview_background_shape">
<stroke android:width="...
Append lines to a file using a StreamWriter
...ter constructor you choose if you append the file, or overwrite it.
C# 4 and above offers the following syntax, which some find more readable:
new StreamWriter("c:\\file.txt", append: true);
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Escape double quotes in a string
...it. This is just a way to tell C# that the character is part of the string and not a string terminator.
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How to generate controller inside namespace in rails
I have namespace admin in controller, and I want to generate a controller inside of the admin folder. How can i do it with a Rails command?
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Sorting data based on second column of a file
I have a file of two columns and n number of rows.
4 Answers
4
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How to construct a set out of list items in python?
I have a list of filenames in python and I would want to construct a set out of all the filenames.
6 Answers
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Plot yerr/xerr as shaded region rather than error bars
... numpy as np
x = np.linspace(0, 30, 30)
y = np.sin(x/6*np.pi)
error = np.random.normal(0.1, 0.02, size=y.shape)
y += np.random.normal(0, 0.1, size=y.shape)
plt.plot(x, y, 'k-')
plt.fill_between(x, y-error, y+error)
plt.show()
See also the matplotlib examples.
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How to get value from form field in django framework?
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Using a form in a view pretty much explains it.
The standard pattern for processing a form in a view looks like this:
def contact(request):
if request.method == 'POST': # If the form has been submitted...
form = ContactForm(request.POST) # A form bound to the POST ...