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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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Maven Install on Mac OS X
I'm trying to install maven through the terminal by following these instructions .
24 Answers
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How to rsync only a specific list of files?
... for me using the --include-from option. Without the --exclude="*" option, all the files in the directory are being synced, with the option, no files are.
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What is :: (double colon) in Python when subscripting sequences?
... @UmarAsghar n means start. so the list start from nth index. Basically, [start:stop:step]
– harryghgim
Sep 1 at 11:42
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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...
Difference between Repository and Service Layer?
... bool Delete(int id);
T Get(int id);
bool SaveChanges();
}
and call Get(id). Repository layer exposes basic CRUD operations.
Service layer exposes business logic, which uses repository. Example service could look like:
public interface IUserService
{
User GetByUserName(string userNa...
Python: split a list based on a condition?
What's the best way, both aesthetically and from a performance perspective, to split a list of items into multiple lists based on a conditional? The equivalent of:
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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...
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...