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Replace all 0 values to NA
...me space for it. E.g.,
data.frame(x = c(1, NA, 2))
# x
# 1 1
# 2 NA
# 3 2
Also, the data frame structure requires all the columns to have the same number of elements so that there can be no "holes" (i.e., NULL values).
Now you could replace zeroes by NULL in a data frame in the sense of com...
What's the difference between ISO 8601 and RFC 3339 Date Formats?
ISO 8601 and RFC 3339 seem to be two formats that are common the web. Should I use one over the other? Is one just an extension? Do I really need to care that bad?
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How to compile without warnings being treated as errors?
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83
Sure, find where -Werror is set and remove that flag. Then warnings will be only warnings.
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What exactly is Java EE?
... maintain. Spring was then a much better alternative to EJB2. But since EJB3 (Java EE 5), the EJB API was much improved based on lessons learnt from Spring. Since CDI (Java EE 6), there's not really a reason to look at again another framework like Spring to make the developers more easy as to develo...
Transpose/Unzip Function (inverse of zip)?
... use the special * operator.
>>> zip(*[('a', 1), ('b', 2), ('c', 3), ('d', 4)])
[('a', 'b', 'c', 'd'), (1, 2, 3, 4)]
The way this works is by calling zip with the arguments:
zip(('a', 1), ('b', 2), ('c', 3), ('d', 4))
… except the arguments are passed to zip directly (after being co...
Rails migrations: Undo default setting for a column
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387
Rails 5+
def change
change_column_default( :table_name, :column_name, from: nil, to: fals...
Global access to Rake DSL methods is deprecated
I am working through the Ruby on Rails 3 tutorial book and typed the following on the command line:
5 Answers
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Use curly braces to initialize a Set in Python
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103
There are two obvious issues with the set literal syntax:
my_set = {'foo', 'bar', 'baz'}
It'...