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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...
Where can I find php.ini?
A few years ago I installed Apache 2.2x and PHP 5.3.1 on a Linux server I maintain. I used .tar.gz's and built them as instructed (instead of rpms and what-have-you). And all was fine.
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Can I force a UITableView to hide the separator between empty cells? [duplicate]
...ra separators from tableview
self.tableView.tableFooterView = [[UIView alloc] initWithFrame:CGRectZero];
}
For previous versions
You could add this to your TableViewController (this will work for any number of sections):
- (CGFloat)tableView:(UITableView *)tableView heightForFooterInSection:...
Padding characters in printf
...E has spaces unless they are already escaped. You'll get one line with two tokens each and then [UP] for every two space-separated tokens in your variable and then a single line at the end with your line text minus the total length of your input string. So be careful, since this could lead to intere...
How to enable PHP's openssl extension to install Composer?
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It is possible that WAMP and Composer are using different PHP installations. Composer will use the PHP set in the PATH environment variable.
If you want to enable the openssl extension to install Composer, first you need to check the location of the PHP installation.
Open a Comm...
Convert a PHP script into a stand-alone windows executable
I want to automate a fairly simple task. For this I have written a small PHP script which I run from the command line using PHP-CLI. Now I want to hand over this script to someone but I do not want to:
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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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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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Upgrading PHP in XAMPP for Windows?
I would like to know how you upgrade PHP in Xampp for Windows? I tried to download the latest PHP version from the main PHP site but when I check (phpinfo) I still get that the previous version is still in use.
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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...