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No secret option provided to Rack::Session::Cookie warning?
I am running Rails 3.2.3, Ruby 1.9 under Fedora 17. I get this warning, when I run rails s , and how do I fix?
7 Answers
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Struct inheritance in C++
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answered Jun 11 '09 at 3:44
Alex MartelliAlex Martelli
724k148148 gold badges11261126 silver badges13241324 bronze badges
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rspec 3 - stub a class method
I am upgrading from rspec 2.99 to rspec 3.0.3 and have converted instance methods to use allow_any_instance_of , but haven't figured out how to stub a class method. I have code like this:
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NameError: global name 'xrange' is not defined in Python 3
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You are trying to run a Python 2 codebase with Python 3. xrange() was renamed to range() in Python 3.
Run the game with Python 2 instead. Don't try to port it unless you know what you are doing, most likely there will be more problems beyond xrange() vs. range().
For the recor...
How to drop columns by name in a data frame
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389
You should use either indexing or the subset function. For example :
R> df <- data.fram...
NameError: global name 'unicode' is not defined - in Python 3
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Python 3 renamed the unicode type to str, the old str type has been replaced by bytes.
if isinstance(unicode_or_str, str):
text = unicode_or_str
decoded = False
else:
text = unicode_or_str.decode(encoding)
decoded =...
Looping over a list in Python
...with sublists in it. I want to print all the sublists with length equal to 3.
4 Answers
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Why is conversion from string constant to 'char*' valid in C but invalid in C++
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3 Answers
3
Active
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Python - abs vs fabs
...(-2))
Out[7]: int
In [8]: type(abs(-2.0))
Out[8]: float
In [9]: type(abs(3+4j))
Out[9]: float
In [10]: type(math.fabs(-2))
Out[10]: float
In [11]: type(math.fabs(-2.0))
Out[11]: float
In [12]: type(math.fabs(3+4j))
---------------------------------------------------------------------------
Type...
dplyr summarise: Equivalent of “.drop=FALSE” to keep groups with zero length in output
....drop argument that does just what you asked for:
df = data.frame(a=rep(1:3,4), b=rep(1:2,6))
df$b = factor(df$b, levels=1:3)
df %>%
group_by(b, .drop=FALSE) %>%
summarise(count_a=length(a))
#> # A tibble: 3 x 2
#> b count_a
#> <fct> <int>
#> 1 1 ...