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How do I create a class instance from a string name in ruby?
...
module One
module Two
class Three
def say_hi
puts "say hi"
end
end
end
end
one = Object.const_get "One"
puts one.class # => Module
three = One::Two.const_get "Three"
puts three.class # => Cl...
pandas GroupBy columns with NaN (missing) values
...
This is mentioned in the Missing Data section of the docs:
NA groups in GroupBy are automatically excluded. This behavior is consistent with R, for example.
One workaround is to use a placeholder before doing the groupby (e.g. -1):
In [...
When and why should I use fragments in Android applications? [duplicate]
...t parent layouts and different classes? Easier to have two parent layouts, one for list and the other for webview. I personaly think your answer is incorrect as you only stated what fragments are used for, not why you should use it instead of one activty hosting two classes. Infact, having one activ...
How can I concatenate regex literals in JavaScript?
...).join("").replace(/(.)(?=.*\1)/g, "");
var regex3 = new RegExp(expression_one.source + expression_two.source, flags);
// regex3 is now /foobar/gy
It's just more wordy than just having expression one and two being literal strings instead of literal regular expressions.
...
How do I force a favicon refresh?
...locally using its own tomcat and I have just changed the favicon for a new one. Problem is that I can not see it in any browser. The old favicon shows up or I get no favicon at all, but not my new one. I do not think this is a Grails issue per se, more an issue with favicons.
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Send string to stdin
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You can use one-line heredoc
cat <<< "This is coming from the stdin"
the above is the same as
cat <<EOF
This is coming from the stdin
EOF
or you can redirect output from a command, like
diff <(ls /bin) <(ls /u...
What are the underlying data structures used for Redis?
...o accomplish what?.
Strings
This is the base type of all the types. It's one of the four types but is also the base type of the complex types, because a List is a list of strings, a Set is a set of strings, and so forth.
A Redis string is a good idea in all the obvious scenarios where you want to...
Separators for Navigation
...list items, position the image to the left of the li, but not on the first one.
For example:
#nav li + li {
background:url('seperator.gif') no-repeat top left;
padding-left: 10px
}
This CSS adds the image to every list item that follows another list item - in other words all of them but ...
How to Convert JSON object to Custom C# object?
...
I prefer the one liners mentioned in other answers.. IMHO.
– RayLoveless
Oct 5 '17 at 20:04
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Deleting lines from one file which are in another file
...atching lines
-x to match whole lines only
-f f2 to get patterns from f2
One can instead use grep -F or fgrep to match fixed strings from f2 rather than patterns (in case you want remove the lines in a "what you see if what you get" manner rather than treating the lines in f2 as regex patterns).
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