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How to drop rows of Pandas DataFrame whose value in a certain column is NaN
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AMC
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answered Nov 16 '12 at 9:34
eumiroeumiro
1...
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 to select rows from a DataFrame based on column values?
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10 Answers
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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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SQL Logic Operator Precedence: And and Or
...e's an example to illustrate:
Declare @x tinyInt = 1
Declare @y tinyInt = 0
Declare @z tinyInt = 0
Select Case When @x=1 OR @y=1 And @z=1 Then 'T' Else 'F' End -- outputs T
Select Case When (@x=1 OR @y=1) And @z=1 Then 'T' Else 'F' End -- outputs F
For those who like to consult references (in al...
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...