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Determine the number of NA values in a column
...nt the number of NA values in a data frame column. Say my data frame is called df , and the name of the column I am considering is col . The way I have come up with is following:
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Add legend to ggplot2 line plot
...range your data frame
library(reshape2)
dd = melt(dd_sub, id=c("fecha"))
All that's left is a simple ggplot command:
ggplot(dd) + geom_line(aes(x=fecha, y=value, colour=variable)) +
scale_colour_manual(values=c("red","green","blue"))
Example plot
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How would you implement an LRU cache in Java?
...y at the back of the iteration order regardless of whether that entry initially exists in the cache)
– Pacerier
Feb 23 '12 at 18:26
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MySQL Error 1153 - Got a packet bigger than 'max_allowed_packet' bytes
I'm importing a MySQL dump and getting the following error.
14 Answers
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Can an Android NFC phone act as an NFC tag?
... a simple old nfc tag? Is there some application I'm not thinking of? Usually, you'd want to emulate something like a transit card, access key, or credit card which would require a secure element (I think, but not sure).
s...
Any reason why scala does not explicitly support dependent types?
...here are path dependent types and I think it is possible to express almost all the features of such languages as Epigram or Agda in Scala, but I'm wondering why Scala does not support this more explicitly like it does very nicely in other areas (say, DSLs) ?
Anything I'm missing like "it is not ne...
Why is the String class declared final in Java?
... have two strings that look alike when "seen as Strings", but that are actually different.
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Declaring array of objects
I have a variable which is an array and I want every element of the array to act as an object by default. To achieve this, I can do something like this in my code.
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REST API Best practices: Where to put parameters? [closed]
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The official rule URIs and the draft sepc were really useful & interesting! :-)
– KajMagnus
Apr 16 '11 at 10:54
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Coffeescript — How to create a self-initiating anonymous function?
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@scribu Well, those two statements are very different, and yours is actually the one that I should have given. Mine assigns the function -> console.log 'this runs right away' to f, then runs it; yours runs the function and then assigns its result to f, as in the original quest...