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Append value to empty vector in R?
... avoided".
As BrodieG mentioned in the comments: it is much better to pre-allocate a vector of the desired length, then set the element values in the loop.
Here are several ways to append values to a vector. All of them are discouraged.
Appending to a vector in a loop
# one way
for (i in 1:le...
Advantages of Binary Search Trees over Hash Tables
... instance, if a hash function has a range R(h) = 0...100, then you need to allocate an array of 100 (pointers-to) elements, even if you are just hashing 20 elements. If you were to use a binary search tree to store the same information, you would only allocate as much space as you needed, as well as...
Is there a documented way to set the iPhone orientation?
...ish to use undocumented methods:
UIViewController *c = [[UIViewController alloc]init];
[self presentModalViewController:c animated:NO];
[self dismissModalViewControllerAnimated:NO];
[c release];
It is sufficient to present and dismiss a vanilla view controller.
Obviously you'll still need to con...
How to get the size of a string in Python?
...rint(len('please anwser my question'))
25
B. To get memory size in bytes allocated to store str object, you can use sys.getsizeof() function
>>> from sys import getsizeof
>>> print(getsizeof('please anwser my question'))
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Python 2:
It gets complicated for Python 2.
A. The...
Creating an R dataframe row-by-row
...g structures is one of the least efficient ways to code in R.
If you can, allocate your entire data.frame up front:
N <- 1e4 # total number of rows to preallocate--possibly an overestimate
DF <- data.frame(num=rep(NA, N), txt=rep("", N), # as many cols as you need
strings...
Change string color with NSAttributedString?
...ttributeName : color };
NSAttributedString *attrStr = [[NSAttributedString alloc] initWithString:string attributes:attrs];
self.scanLabel.attributedText = attrStr;
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How to get current time and date in C++?
...
@Petr you only need to call delete on memory allocated with new.
– iheanyi
Aug 15 '14 at 16:52
4
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IE 8: background-size fix [duplicate]
...Method='scale')";
However, this scales the entire image to fit in the allocated area. So
if your using a sprite, this may cause issues.
Caution
The filter has a flaw, any links inside the allocated area are no longer clickable.
...
C: differences between char pointer and array [duplicate]
...sion is actually just a shortcut for array instantiation. So the array is allocated in the stack, and then loaded with the string's data.
– Walt W
Aug 26 '09 at 17:42
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Draw text in OpenGL ES
...'ll find the answer in time, but does your implementation use any run time allocations?
– Nick Hartung
Dec 27 '12 at 18:16
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