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Make xargs handle filenames that contain spaces
...cters (tabs, spaces, new lines) as delimiters.
You can narrow it down only for the new line characters ('\n') with -d option like this:
ls *.mp3 | xargs -d '\n' mplayer
It works only with GNU xargs.
For BSD systems, use the -0 option like this:
ls *.mp3 | xargs -0 mplayer
This method is simpler an...
What is the right way to check for a null string in Objective-C?
... since [NSNull null] is documented to be a singleton so you can just check for pointer equality. See Topics for Cocoa: Using Null.
So a good test might be:
if (title == (id)[NSNull null] || title.length == 0 ) title = @"Something";
Note how you can use the fact that even if title is nil, title.l...
Determine the data types of a data frame's columns
...X3
"numeric" "integer" "logical" "factor"
Using str() gets you that information plus extra goodies (such as the levels of your factors and the first few values of each variable):
str(my.data)
'data.frame': 5 obs. of 4 variables:
$ y : num 1.03 1.599 -0.818 0.872 -2.682
$ x1: int 1 2 3 4 ...
Which MySQL data type to use for storing boolean values
...esn't seem to have any 'boolean' data type, which data type do you 'abuse' for storing true/false information in MySQL?
13 ...
Replace all elements of Python NumPy Array that are greater than some value
...es at indexes which are multiple of given n, like a[2],a[4],a[6],a[8]..... for n=2?
– lavee_singh
Oct 7 '15 at 19:01
1...
HTML5 canvas ctx.fillText won't do line breaks?
...tes the lower-level drawing functionality from what you can already do (perform the necessary measurements). Also, you can know the text height simply by providing the text size in pixels; in other words: context.font = "16px Arial"; - you have the height there; the width is the only one that is dyn...
Drawing a dot on HTML5 canvas [duplicate]
Drawing a line on the HTML5 canvas is quite straightforward using the context.moveTo() and context.lineTo() functions.
...
Shortest distance between a point and a line segment
...t is 0 the projection falls right on v; if it's 1, it's on w; if it's 0.5, for example, then it's halfway between. If t is less than 0 or greater than 1 it falls on the line past one end or the other of the segment. In that case the distance to the segment will be the distance to the nearer end.
...
What is q=0.5 in Accept* HTTP headers?
...ciated quality value which represents an estimate of the user's preference for the languages specified by that range. The quality value defaults to "q=1". For example,
Accept-Language: da, en-gb;q=0.8, en;q=0.7
would mean: "I prefer Danish, but will accept British English and other types of Engli...
How does the socket API accept() function work?
The socket API is the de-facto standard for TCP/IP and UDP/IP communications (that is, networking code as we know it). However, one of its core functions, accept() is a bit magical.
...