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Fetch frame count with ffmpeg
...ult=nokey=1:noprint_wrappers=1 input.mp4
This is a fast method.
Not all formats (such as Matroska) will report the number of frames resulting in the output of N/A. See the other methods listed below.
ffprobe: Count the number of frames
ffprobe -v error -count_frames -select_streams v:0 -show_e...
How to append rows to an R data frame
..., I'll share one more suggestion: Preallocate vectors of the type you want for each column, insert values into those vectors, and then, at the end, create your data.frame.
Continuing with Julian's f3 (a preallocated data.frame) as the fastest option so far, defined as:
# pre-allocate space
f3 <...
Why are these numbers not equal?
...nted exactly in binary?
Is floating point math broken?
Canonical duplicate for "floating point is inaccurate" (a meta discussion about a canonical answer for this issue)
Comparing scalars
The standard solution to this in R is not to use ==, but rather the all.equal function. Or rather, since all...
how to find host name from IP with out login to the host
...o run sudo yum install bind-utils first. this will install nslookup lookup for you
– lfender6445
Jul 5 '15 at 0:10
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What's the point of malloc(0)?
..., but still pass the "artist" variable to a call to free() without worry. For practical purposes, it's pretty much the same as doing:
artist = NULL;
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Maven in Eclipse: step by step installation [closed]
... Maven site reading the 5- and 30-minute tutorials, and trialing Maven out for the first time.
13 Answers
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Drop shadow for PNG image in CSS
I have a PNG image, that has free form (non square).
15 Answers
15
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How to create a sequence of integers in C#?
...
You could create a simple function. This would work for a more complicated sequence. Otherwise the Enumerable.Range should do.
IEnumerable<int> Sequence(int n1, int n2)
{
while (n1 <= n2)
{
yield return n1++;
}
}
...
Why does this code using random strings print “hello world”?
... would be 1 in 27^6 (387,420,489) of getting the sequence you were looking for -- so it's pretty impressive but not quite mind-blowing!
– Russell Borogove
Mar 3 '13 at 7:48
18
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How does the static modifier affect this code?
...icit initialization" happens as part of declaration. Declaration happens before assignment no matter what order you present them in. A obj = new A(); int num1; int num2 = 0; gets turned into this: A obj; int num1; int num2; obj = new A(); num2 = 0;. Java does this so num1, num2 are defined by the ti...