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Short description of the scoping rules?
...
426
Actually, a concise rule for Python Scope resolution, from Learning Python, 3rd. Ed.. (These ru...
Why does this loop produce “warning: iteration 3u invokes undefined behavior” and output more than 4
...cout << i*1000000000 << std::endl;
^
a.cpp:9:2: note: containing loop
for (int i = 0; i < 4; ++i)
^
The only way we can analyze what the program is doing, is by reading the generated assembly code.
Here is the full assembly listing:
.file "a.cpp"
.s...
Capturing Groups From a Grep RegEx
...ing stored in a variable
else
echo "$f doesn't match" >&2 # this could get noisy if there are a lot of non-matching files
fi
done
It's better to put the regex in a variable. Some patterns won't work if included literally.
This uses =~ which is Bash's regex match operator. ...
Changing the “tick frequency” on x or y axis in matplotlib?
...rt numpy as np
import matplotlib.pyplot as plt
x = [0,5,9,10,15]
y = [0,1,2,3,4]
plt.plot(x,y)
plt.xticks(np.arange(min(x), max(x)+1, 1.0))
plt.show()
(np.arange was used rather than Python's range function just in case min(x) and max(x) are floats instead of ints.)
The plt.plot (or ax.plot...
Pointers in Python?
... know Python doesn't have pointers, but is there a way to have this yield 2 instead
9 Answers
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Convert a list to a data frame
I have a nested list of data. Its length is 132 and each item is a list of length 20. Is there a quick way to convert this structure into a data frame that has 132 rows and 20 columns of data?
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How to suppress Update Links warning?
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UPDATE:
After all the details summarized and discussed, I spent 2 fair hours in checking the options, and this update is to dot all is.
Preparations
First of all, I performed a clean Office 2010 x86 install on Clean Win7 SP1 Ultimate x64 virtual machine powered by VMWare (this is usual ...
Is there an R function for finding the index of an element in a vector?
...rks on vectors :
x <- sample(1:10)
x
# [1] 4 5 9 3 8 1 6 10 7 2
match(c(4,8),x)
# [1] 1 5
match only returns the first encounter of a match, as you requested. It returns the position in the second argument of the values in the first argument.
For multiple matching, %in% is the way to...
Is there an easy way to create ordinals in C#?
...
21 Answers
21
Active
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Convert duration to hours:minutes:seconds (or similar) in Rails 3 or Ruby
...what a nub!
– cydonia
Nov 14 '10 at 2:13
1
yeah, those examples are daft
– ...