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Automatically expanding an R factor into a collection of 1/0 indicator variables for every factor le
...vel, there is an associated column in a new data frame, which contains a 1/0 indicator. E.g., suppose I have:
8 Answers
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How to use glOrtho() in OpenGL?
...window is resized:
glMatrixMode(GL_PROJECTION);
glLoadIdentity();
glOrtho(0.0f, windowWidth, windowHeight, 0.0f, 0.0f, 1.0f);
This will remap the OpenGL coordinates into the equivalent pixel values (X going from 0 to windowWidth and Y going from 0 to windowHeight). Note that I've flipped the Y va...
How does the Brainfuck Hello World actually work?
...
+100
1. Basics
To understand Brainfuck you must imagine infinite array of cells initialized by 0 each.
...[0][0][0][0][0]...
When brai...
How to select rows from a DataFrame based on column values?
...
10 Answers
10
Active
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Syntax for creating a two-dimensional array
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Try the following:
int[][] multi = new int[5][10];
... which is a short hand for something like this:
int[][] multi = new int[5][];
multi[0] = new int[10];
multi[1] = new int[10];
multi[2] = new int[10];
multi[3] = new int[10];
multi[4] = new int[10];
Note that every...
What is Bit Masking?
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250
A mask defines which bits you want to keep, and which bits you want to clear.
Masking is the ac...
How can I get the current network interface throughput statistics on Linux/UNIX? [closed]
...phs for the current network utilisation on specific interfaces, such as eth0. How can I return that information at the command line on Linux/UNIX?
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Center a map in d3 given a geoJSON object
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+300
The following seems to do approximately what you want. The scaling seems to be ok. When applying it to my map there is a small offset...
What is the most pythonic way to check if an object is a number?
...cimal import Decimal
... from fractions import Fraction
... for n in [2, 2.0, Decimal('2.0'), complex(2, 0), Fraction(2, 1), '2']:
... print(f'{n!r:>14} {isinstance(n, Number)}')
2 True
2.0 True
Decimal('2.0') True
(2+0j) True
Fraction(2, 1) True
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Numbering rows within groups in a data frame
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edited Mar 14 '17 at 22:06
Frank
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answered Oc...