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Append an object to a list in R in amortized constant time, O(1)?
...oldlist, list(someobj))
In general, R types can make it hard to have one and just one idiom for all types and uses.
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OS X Terminal Colors [closed]
...rminal colors.
Edit your .bash_profile (since OS X 10.8) — or (for 10.7 and earlier): .profile or .bashrc or /etc/profile (depending on availability) — in your home directory and add following code:
export CLICOLOR=1
export LSCOLORS=GxFxCxDxBxegedabagaced
CLICOLOR=1 simply enables coloring o...
Omit rows containing specific column of NA
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You could use the complete.cases function and put it into a function thusly:
DF <- data.frame(x = c(1, 2, 3), y = c(0, 10, NA), z=c(NA, 33, 22))
completeFun <- function(data, desiredCols) {
completeVec <- complete.cases(data[, desiredCols])
return(data...
Count number of files within a directory in Linux? [closed]
... the top adding up the file sizes for a total amount. You should use ls -1 and not the ls -l. Also if one wants hidden files but without the directories . and .. you should use ls -1A | wc -l
– Daniel Biegler
Mar 7 '18 at 11:02
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Sorting a vector of custom objects
...ting a vector containing custom (i.e. user defined) objects.
Probably, standard STL algorithm sort along with a predicate (a function or a function object) which would operate on one of the fields (as a key for sorting) in the custom object should be used.
Am I on the right track?
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What does enumerate() mean?
...is produced with (counter, element); the for loop binds that to row_number and row, respectively.
Demo:
>>> elements = ('foo', 'bar', 'baz')
>>> for elem in elements:
... print elem
...
foo
bar
baz
>>> for count, elem in enumerate(elements):
... print count, ele...
How do I make python wait for a pressed key?
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@Solarsaturn9 and an increasing and large number do not. Thus this answer did not work for me, and the many other that come here.
– ctrl-alt-delor
Oct 22 '15 at 22:00
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How to delete a character from a string using Python
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Given that the questioner is brand new to python, it might be worth noting that while in version 2.X python the "/" operator returns an integer (truncated towards zero), in version 3.X python you should use "//" instead. Also, the line from __future__ impo...
Node.js - Find home directory in platform agnostic way
...indows a user's home directory might be C:\Users[USERNAME] or C:\Documents and Settings[USERNAME] depending on which version of Windows is being used. On Unix this isn't an issue.
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Vim: Move window left/right?
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Ctrl w gives you the "windows command mode", allowing the following modifiers:
Ctrl w + R - To rotate windows up/left.
Ctrl w + r - To rotate windows down/right.
You can also use the "windows command mode" with navigation keys to change a window's positio...