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How to append rows to an R data frame
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Not knowing what you are trying to do, 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, def...
Why do most C developers use define instead of const? [duplicate]
...til runtime and can only be used for automatic variables (i.e. can only be allocated on the stack).
– Bart van Ingen Schenau
Oct 27 '10 at 12:44
4
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Best way to remove from NSMutableArray while iterating?
.... That may be true (although what about the memory and processing cost of allocating a new array, and discarding the old one?) but even if it's faster it may not be as big a deal as it would be for a naive implementation, because NSArrays do not behave like "normal" arrays. They talk the talk but ...
NSURLRequest setting the HTTP header
...NSMutableURLRequest
NSMutableURLRequest* request = [[[NSMutableURLRequest alloc] initWithURL:url]
autorelease];
[request setValue:VALUE forHTTPHeaderField:@"Field You Want To Set"];
or to add a header:
[request addValue:VALUE forHTTPHeaderField:@"Field You Want T...
Best way to do multiple constructors in PHP
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<?php
class Student
{
public function __construct() {
// allocate your stuff
}
public static function withID( $id ) {
$instance = new self();
$instance->loadByID( $id );
return $instance;
}
public static function withRow( array $row ) {
...
Should I pass a shared_ptr by reference? [duplicate]
...t binary size of the executable image a bit due to RTTI stuff, whether the allocation would actually benefit the runtime performance or not. This should not be a problem for desktop/server platforms, but may be a problem for embedded environment with extremely limited resources.
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Pointer vs. Reference
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@MSalters: If you're going to allocate the memory inside the function (which I think is what you mean), then why not just return a pointer to the allocated memory?
– Kleist
Feb 16 '11 at 9:27
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“java.lang.OutOfMemoryError : unable to create new native Thread”
...e JVM asks for a new thread from the OS. Whenever the underlying OS cannot allocate a new native thread, this OutOfMemoryError will be thrown. The exact limit for native threads is very platform-dependent thus its recommend to find out those limits by running a test similar to the below link example...
What is copy-on-write?
...ncurrency sorts of problems. In ZFS, for example, data blocks on disk are allocated copy-on-write; as long as there are no changes, you keep the original blocks; a change changed only the affected blocks. This means the minimum number of new blocks are allocated.
These changes are also usually im...
在 App Inventor 2 中使用图像 · App Inventor 2 中文网
...crashes[a] when they try to run it, with an error message like:
Failed to allocate a 25165836 byte allocation with 3395432 free bytes and 3MB until OOM
What’s happening here is that the app is is running out of memory (OOM). In the case of the message above, the phone is trying to allocate 25 m...