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Python 3.x rounding behavior
I was just re-reading What’s New In Python 3.0 and it states:
11 Answers
11
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Regex group capture in R with multiple capture-groups
...roup in the match (and one for the whole match):
> s = c("(sometext :: 0.1231313213)", "(moretext :: 0.111222)")
> str_match(s, "\\((.*?) :: (0\\.[0-9]+)\\)")
[,1] [,2] [,3]
[1,] "(sometext :: 0.1231313213)" "sometext" "0.1231313213"
[2,] "(moretex...
Vagrant reverse port forwarding?
...ROR -o IdentitiesOnly=yes -i ~/.vagrant.d/insecure_private_key vagrant@127.0.0.1
SSH supports forwarding ports in the direction you want with the -R guestport:host:hostport option. So, if you wanted to connect to port 12345 on the guest and have it forwarded to localhost:80, you would use this comm...
Numpy: Divide each row by a vector element
...combined with broadcasting:
In [6]: data - vector[:,None]
Out[6]:
array([[0, 0, 0],
[0, 0, 0],
[0, 0, 0]])
In [7]: data / vector[:,None]
Out[7]:
array([[1, 1, 1],
[1, 1, 1],
[1, 1, 1]])
share
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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 ...
How do you round a floating point number in Perl?
... and floor()?
Trig functions?
Remember that int() merely truncates toward 0. For rounding to a certain number of digits, sprintf() or printf() is usually the easiest
route.
printf("%.3f", 3.1415926535); # prints 3.142
The POSIX module (part of the standard Perl distribution) implement...
How to detect if a script is being sourced
...
This seems to be portable between Bash and Korn:
[[ $_ != $0 ]] && echo "Script is being sourced" || echo "Script is a subshell"
A line similar to this or an assignment like pathname="$_" (with a later test and action) must be on the first line of the script or on the line ...
How can I confirm a database is Oracle & what version it is using SQL?
...
10 Answers
10
Active
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Pandas - Get first row value of a given column
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To select the ith row, use iloc:
In [31]: df_test.iloc[0]
Out[31]:
ATime 1.2
X 2.0
Y 15.0
Z 2.0
Btime 1.2
C 12.0
D 25.0
E 12.0
Name: 0, dtype: float64
To select the ith value in the Btime column you could use:
In [30]: df_te...
Check for current Node Version
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206
Try to look at process.version property.
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