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Docker how to change repository name or rename image?
...host OS and Docker version? I suspect that something about your Docker installation is modifying the tag instruction.
– Andy
Feb 18 '16 at 2:41
27
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Selecting multiple columns in a pandas dataframe
...).
df1 = df[['a', 'b']]
Alternatively, if it matters to index them numerically and not by their name (say your code should automatically do this without knowing the names of the first two columns) then you can do this instead:
df1 = df.iloc[:, 0:2] # Remember that Python does not slice inclusive of...
Generic type conversion FROM string
...es" for another class. These properties simply have a name and a value. Ideally, what I would like is to be able to add typed properties, so that the "value" returned is always of the type that I want it to be.
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In Django - Model Inheritance - Does it allow you to override a parent model's attribute?
...ld instances (at least,
not at the moment). If a base class has a field called author, you
cannot create another model field called author in any class that
inherits from that base class.
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Pick a random element from an array
... Int? Also, why doesn't Swift offer an Int alternative to this function or allow a user to specify what type of integer they would like returned?
– Austin A
Sep 27 '14 at 21:10
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What is the most efficient way to store a list in the Django models?
...
This is probably what I will end up doing, but I was really hoping the underlying structure for this would have been built in. I guess I am to o lazy.
– grieve
Jul 10 '09 at 16:11
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Are JavaScript strings immutable? Do I need a “string builder” in JavaScript?
...ved would be the fastest way, though I kept thinking that adding a method call may make it slower...
function StringBuilder() {
this._array = [];
this._index = 0;
}
StringBuilder.prototype.append = function (str) {
this._array[this._index] = str;
this._index++;
}
StringBuilder.pro...
Counting the Number of keywords in a dictionary in python
... the len() function.
> a = {'foo':42, 'bar':69}
> len(a)
2
To get all the distinct words (i.e. the keys), use the .keys() method.
> list(a.keys())
['foo', 'bar']
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Matplotlib (pyplot) savefig outputs blank image
...values that depend whether or not T0 exists.
Second, after plt.show() is called, a new figure is created. To deal with this, you can
Call plt.savefig('tessstttyyy.png', dpi=100) before you call plt.show()
Save the figure before you show() by calling plt.gcf() for "get current figure", then you ca...
How to display all methods of an object?
I want to know how to list all methods available for an object like for example:
8 Answers
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