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'float' vs. 'double' precision
... exponent and significand). The IEEE 754 standard (used by most compilers) allocate relatively more bits for the significand than the exponent (23 to 9 for float vs. 52 to 12 for double), which is why the precision is more than doubled.
1: Section 5.2.4.2.2 ( http://www.open-std.org/jtc1/sc22/wg14/...
C++ STL Vectors: Get iterator from index?
...s of a vector are stored contiguously, meaning that if v is a vector<T, Allocator> where T is some type other than bool, then it obeys the identity &v[n] == &v[0] + n for all 0 <= n < v.size()"
– yves Baumes
Sep 17 '12 at 21:07
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How would one write object-oriented code in C? [closed]
...takes uninitialized memory
struct stack * (* operator_new)(); // This allocates a new struct, passes it to construct, and then returns it
void (*push)(struct stack * this, thing * t); // Pushing t onto this stack
thing * (*pop)(struct stack * this); // Pops the top thing off the stack...
Best practices: throwing exceptions from properties
...t won't; it could easily be calling code that does. Even the simple act of allocating a new object (like a string) could result in exceptions. You should always write your code defensively and expect exceptions from anything you invoke.
...
How to programmatically send SMS on the iPhone?
...ssageComposeViewController *controller = [[[MFMessageComposeViewController alloc] init] autorelease];
if([MFMessageComposeViewController canSendText])
{
controller.body = @"SMS message here";
controller.recipients = [NSArray arrayWithObjects:@"1(234)567-8910", nil];
controller.messageCom...
Why isn't sizeof for a struct equal to the sum of sizeof of each member?
...f a (non-union) class declared without an intervening access-specifier are allocated so that later members have higher addresses within a class object"
– jfs
Apr 10 '17 at 20:40
...
How to compare 2 files fast using .NET?
...e .NET GC (because it's fundamentally optimized to keep small, short-lived allocations extremely cheap), and in fact could even be optimal when file sizes are expected to be less than 85K, because using a minimum of user code (as shown here) implies maximally delegating file performance issues to th...
What is database pooling?
...e connections to multiple servers and multiple user accounts, they may pre-allocate some baseline of connections so some are ready immediately, and they may actually close old connections when the usage pattern quietens down.
...
What are the advantages of NumPy over regular Python lists?
... (4 for type pointer, 4 for reference count, 4 for value -- and the memory allocators rounds up to 16). A NumPy array is an array of uniform values -- single-precision numbers takes 4 bytes each, double-precision ones, 8 bytes. Less flexible, but you pay substantially for the flexibility of standard...
Tuples( or arrays ) as Dictionary keys in C#
...s are value types (structs), not reference types, so they avoid the memory allocation and garbage collection costs. Also, they offer conciser and more intuitive syntax, allowing for their fields to be named if you so wish. They also implement the IEquatable<T> interface needed for the dictiona...