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Looping over a list in Python
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Try this,
x in mylist is better and more readable than x in mylist[:] and your len(x) should be equal to 3.
>>> mylist = [[1,2,3],[4,5,6,7],[8,9,10]]
>>> for x in mylist:
... if len(x)==3:
... print x
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[1, 2, 3]
[8, 9, 10]
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What is the point of Lookup?
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It's a cross between an IGrouping and a dictionary. It lets you group items together by a key, but then access them via that key in an efficient manner (rather than just iterating over them all, which is what GroupBy lets you do).
For example, you could take...
How to make graphics with transparent background in R using ggplot2?
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Updated with the theme() function, ggsave() and the code for the legend background:
df <- data.frame(y = d, x = 1, group = rep(c("gr1", "gr2"), 50))
p <- ggplot(df) +
stat_boxplot(aes(x = x, y = y, color = group),
fill = "transparent" # for the...
How to get numbers after decimal point?
...On a Raspberry Pi this method x%1 was almost twice as fast as the x-int(x) and modf(x)[0] methods (the timings were 980ns, 1.39us, and 1.47us averaged over 1000000 runs). My value for x was always positive so I did not have to worry about that.
– coderforlife
J...
How to ignore files which are in repository?
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@Nimbus147: it shouldn't be an issue, and any changes on that file will still be ignored (ie not added/committed).
– VonC
Aug 29 '11 at 16:57
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What do you call the -> operator in Ruby?
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In Ruby Programming Language ("Methods, Procs, Lambdas, and Closures"), a lambda defined using -> is called lambda literal.
succ = ->(x){ x+1 }
succ.call(2)
The code is equivalent to the following one.
succ = lambda { |x| x + 1 }
succ.call(2)
Informally, I have heard...
Java inner class and static nested class
What is the main difference between an inner class and a static nested class in Java? Does design / implementation play a role in choosing one of these?
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emacs, unsplit a particular window split
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I've been using Emacs for 30 years and never noticed this feature!
– Blisterpeanuts
Jun 10 at 12:59
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Routing with Multiple Parameters using ASP.NET MVC
Our company is developing an API for our products and we are thinking about using ASP.NET MVC. While designing our API, we decided to use calls like the one below for the user to request information from the API in XML format:
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Why does git perform fast-forward merges by default?
...ex history, non-fast-forward merging may make the history easier to understand, and make it easier to revert a group of commits.
Warning: Non-fast-forwarding has potential side effects as well. Please review https://sandofsky.com/blog/git-workflow.html, avoid the 'no-ff' with its "checkpoint commit...