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How do I call one constructor from another in Java?
Is it possible to call a constructor from another (within the same class, not from a subclass)? If yes how? And what could be the best way to call another constructor (if there are several ways to do it)?
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How can I make pandas dataframe column headers all lowercase?
...data.columns]
example:
>>> data = pd.DataFrame({'A':range(3), 'B':range(3,0,-1), 'C':list('abc')})
>>> data
A B C
0 0 3 a
1 1 2 b
2 2 1 c
>>> data.columns = map(str.lower, data.columns)
>>> data
a b c
0 0 3 a
1 1 2 b
2 2 1 c
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CMake: How to build external projects and include their targets
I have a Project A that exports a static library as a target:
5 Answers
5
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PHP mkdir: Permission denied problem
I am trying to create a directory with PHP mkdir function but I get an error as follows: Warning: mkdir() [function.mkdir]: Permission denied in ... . How to settle down the problem?
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How to render a PDF file in Android
Android does not have PDF support in its libraries. Is there any way to render PDF files in the Android applications?
9 Ans...
Regular expression to stop at first match
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You need to make your regular expression non-greedy, because by default, "(.*)" will match all of "file path/level1/level2" xxx some="xxx".
Instead you can make your dot-star non-greedy, which will make it match as few characters as possible:
/location="(.*?)"/
Adding a ? o...
What is the difference between \r and \n?
... different? I think it has something to do with Unix vs. Windows vs. Mac, but I'm not sure exactly how they're different, and which to search for/match in regexes.
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List comprehension: Returning two (or more) items for each item
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>>> from itertools import chain
>>> f = lambda x: x + 2
>>> g = lambda x: x ** 2
>>> list(chain.from_iterable((f(x), g(x)) for x in range(3)))
[2, 0, 3, 1, 4, 4]
Timings:
from timeit impo...
How to get the parent dir location
this code is get the templates/blog1/page.html in b.py:
11 Answers
11
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Difference between float and decimal data type
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This is what I found when I had this doubt.
mysql> create table numbers (a decimal(10,2), b float);
mysql> insert into numbers values (100, 100);
mysql> select @a := (a/3), @b := (b/3), @a * 3, @b * 3 from numbers \G
*************************** 1. row ***...