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Linear Regression and group by in R
...ction. My data is an annual time series with one field for year (22 years) and another for state (50 states). I want to fit a regression for each state so that at the end I have a vector of lm responses. I can imagine doing for loop for each state then doing the regression inside the loop and adding...
Finding current executable's path without /proc/self/exe
...ecutable or a name that was found using $PATH.
Some shells, including bash and ksh, set the environment variable "_" to the full path of the executable before it is executed. In that case you can use getenv("_") to get it. However this is unreliable because not all shells do this, and it could be ...
RegEx for matching UK Postcodes
...
I'd recommend taking a look at the UK Government Data Standard for postcodes [link now dead; archive of XML, see Wikipedia for discussion]. There is a brief description about the data and the attached xml schema provides a regular expression. It may not be exactly what you want bu...
SQL Logic Operator Precedence: And and Or
...
And has precedence over Or, so, even if a <=> a1 Or a2
Where a And b
is not the same as
Where a1 Or a2 And b,
because that would be Executed as
Where a1 Or (a2 And b)
and what you want, to make them the same,...
Are list-comprehensions and functional functions faster than “for loops”?
... in Python, is a list-comprehension, or functions like map() , filter() and reduce() faster than a for loop? Why, technically, they run in a C speed , while the for loop runs in the python virtual machine speed ?.
...
How to pretty-print a numpy.array without scientific notation and with given precision?
...printoptions to set the precision of the output:
import numpy as np
x=np.random.random(10)
print(x)
# [ 0.07837821 0.48002108 0.41274116 0.82993414 0.77610352 0.1023732
# 0.51303098 0.4617183 0.33487207 0.71162095]
np.set_printoptions(precision=3)
print(x)
# [ 0.078 0.48 0.413 0.83 ...
Differences between Oracle JDK and OpenJDK
Are there any crucial differences between Oracle and OpenJDK?
11 Answers
11
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How to define a two-dimensional array?
...sion that could arise with the indexing, if you use "x" for both the inner and outer lists, and want a non-square Matrix.
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Draw a perfect circle from user's touch
...e, lines, etc, whatever came to his mind).
Then he started to draw circles and then he asked me to make it "good circle" (from my understanding: make the drawn circle perfectly round, as we know
no matter how stable we try to draw something with our finger on the screen, a circle is never really as...
What killed my process and why?
... runs as a background process on Linux. It is currently started at the command line in a Terminal window.
14 Answers
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