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Array slicing in Ruby: explanation for illogical behaviour (taken from Rubykoans.com)
...emselves):
:peanut :butter :and :jelly
0 1 2 3 4
4 is still within the array, just barely; if you request 0 elements, you get the empty end of the array. But there is no index 5, so you can't slice from there.
When you do index (like array[4]), you are pointin...
What is the fastest integer division supporting division by zero no matter what the result is?
... movl %eax, %ecx
popl %ebp
movl %edx, %eax
sarl $31, %edx
idivl %ecx
ret
As this turned out to be such a popular question and answer, I'll elaborate a bit more. The above example is based on programming idiom that a compiler recognizes. In the above case a boole...
Converting a column within pandas dataframe from int to string
...hape(5,2),columns=list('AB'))
In [17]: df
Out[17]:
A B
0 0 1
1 2 3
2 4 5
3 6 7
4 8 9
In [18]: df.dtypes
Out[18]:
A int64
B int64
dtype: object
Convert a series
In [19]: df['A'].apply(str)
Out[19]:
0 0
1 2
2 4
3 6
4 8
Name: A, dtype: object
In [20]: df['A...
How to compare two strings in dot separated version format in Bash?
...;
1) op='>';;
2) op='<';;
esac
if [[ $op != $3 ]]
then
echo "FAIL: Expected '$3', Actual '$op', Arg1 '$1', Arg2 '$2'"
else
echo "Pass: '$1 $op $2'"
fi
}
# Run tests
# argument table format:
# testarg1 testarg2 expected_relationship
ech...
Connect to a locally built Jekyll Server using mobile devices in the LAN
...
183
Try jekyll serve --host=0.0.0.0 when you invoke Jekyll on the command line.
That will make Jeky...
Validate phone number with JavaScript
...ctly. It validates that the phone number is in one of these formats:
(123) 456-7890 or 123-456-7890
26 Answers
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How can I check if a string represents an int, without using try/except?
Is there any way to tell whether a string represents an integer (e.g., '3' , '-17' but not '3.14' or 'asfasfas' ) Without using a try/except mechanism?
...
Moving matplotlib legend outside of the axis makes it cutoff by the figure box
...
3 Answers
3
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Find the max of two or more columns with pandas
...>>> import pandas as pd
>>> df = pd.DataFrame({"A": [1,2,3], "B": [-2, 8, 1]})
>>> df
A B
0 1 -2
1 2 8
2 3 1
>>> df[["A", "B"]]
A B
0 1 -2
1 2 8
2 3 1
>>> df[["A", "B"]].max(axis=1)
0 1
1 8
2 3
and so:
>>> df["C"] = ...
while (1) vs. while(True) — Why is there a difference (in python 2 bytecode)?
...
3 Answers
3
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