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how to generate migration to make references polymorphic
...oProducts < ActiveRecord::Migration
def up
change_table :products do |t|
t.references :imageable, polymorphic: true
end
end
def down
change_table :products do |t|
t.remove_references :imageable, polymorphic: true
end
end
end
...
A std::map that keep track of the order of insertion?
...nt> that stores an integer value to an unique string identifier, and I do look up with the string. It does mostly what I want, except for that it does not keep track of the insertion order. So when I iterate the the map to print out the values, they are sorted according to the string; but I want...
How to drop into REPL (Read, Eval, Print, Loop) from Python code
...
You can do it even simpler than that: import code; code.interact(local=locals())
– Steven Kryskalla
Sep 9 '09 at 4:17
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Remove unwanted parts from strings in a column
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@eumiro how do you apply this result if iterating each column?
– medev21
Sep 1 '16 at 19:50
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Multiple constructors in python? [duplicate]
...nly in the number of arguments using default arguments is the right way to do it. If you want to be able to pass in different kinds of argument I would try to avoid the isinstance-based approach mentioned in another answer, instead using keyword arguments. If using just keyword arguments becomes unw...
SharedPreferences.onSharedPreferenceChangeListener not being called consistently
...ged(SharedPreferences prefs, String key) {
// Implementation
}
});
do this:
// Use instance field for listener
// It will not be gc'd as long as this instance is kept referenced
listener = new SharedPreferences.OnSharedPreferenceChangeListener() {
public void onSharedPreferenceChanged(Sha...
pandas dataframe columns scaling with sklearn
...ply sklearn's min_max_scaler to some of the columns. Ideally, I'd like to do these transformations in place, but haven't figured out a way to do that yet. I've written the following code that works:
...
How can I present a file for download from an MVC controller?
...bForms, I would normally have code like this to let the browser present a "Download File" popup with an arbitrary file type, like a PDF, and a filename:
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Load multiple packages at once
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Several permutations of your proposed functions do work -- but only if you specify the character.only argument to be TRUE. Quick example:
lapply(x, require, character.only = TRUE)
share
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master branch and 'origin/master' have diverged, how to 'undiverge' branches'?
...ehow my master and my origin/master branch have diverged.
I actually don't want them to diverge.
13 Answers
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