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What does “fragment” mean in ANTLR?
...r:
NUMBER: DIGITS | OCTAL_DIGITS | HEX_DIGITS;
fragment DIGITS: '1'..'9' '0'..'9'*;
fragment OCTAL_DIGITS: '0' '0'..'7'+;
fragment HEX_DIGITS: '0x' ('0'..'9' | 'a'..'f' | 'A'..'F')+;
In this example, matching a NUMBER will always return a NUMBER to the lexer, regardless of if it matched "1234", "...
Fastest way to reset every value of std::vector to 0
...at's the fastest way to reset every value of a std::vector<int> to 0 and keeping the vectors initial size ?
6 Answ...
Is it possible to set a number to NaN or infinity?
...
– David Heffernan
Mar 25 '11 at 22:30
2
...
Is False == 0 and True == 1 an implementation detail or is it guaranteed by the language?
Is it guaranteed that False == 0 and True == 1 , in Python (assuming that they are not reassigned by the user)? For instance, is it in any way guaranteed that the following code will always produce the same results, whatever the version of Python (both existing and, likely, future ones)?
...
How can you profile a Python script?
...e.bat':
python -m cProfile %1
So all I have to do is run:
profile euler048.py
And I get this:
1007 function calls in 0.061 CPU seconds
Ordered by: standard name
ncalls tottime percall cumtime percall filename:lineno(function)
1 0.000 0.000 0.061 0.061 <string>:1(&lt...
Creating a Pandas DataFrame from a Numpy array: How do I specify the index column and column headers
...
350
You need to specify data, index and columns to DataFrame constructor, as in:
>>> pd.Da...
How to calculate the angle between a line and the horizontal axis?
... the positive Y axis at P1).
angleInDegrees = arctan(deltaY / deltaX) * 180 / PI
But arctan may not be ideal, because dividing the differences this way will erase the distinction needed to distinguish which quadrant the angle is in (see below). Use the following instead if your language includes ...
Razor HtmlHelper Extensions (or other namespaces for views) Not Found
...r.Configuration.RazorWebSectionGroup, System.Web.WebPages.Razor, Version=1.0.0.0, Culture=neutral, PublicKeyToken=31BF3856AD364E35">
<section name="host" type="System.Web.WebPages.Razor.Configuration.HostSection, System.Web.WebPages.Razor, Version=1.0.0.0, Culture=neutral, PublicKeyToken=3...
Days between two dates? [duplicate]
...er of days:
>>> from datetime import date
>>> a = date(2011,11,24)
>>> b = date(2011,11,17)
>>> a-b
datetime.timedelta(7)
>>> (a-b).days
7
And it works with datetimes too — I think it rounds down to the nearest day:
>>> from datetime import...
Numpy - add row to array
...pare its row to a number: i < 3?
EDIT after OP's comment:
A = array([[0, 1, 2], [0, 2, 0]])
X = array([[0, 1, 2], [1, 2, 0], [2, 1, 2], [3, 2, 0]])
add to A all rows from X where the first element < 3:
import numpy as np
A = np.vstack((A, X[X[:,0] < 3]))
# returns:
array([[0, 1, 2],
...