Tom wrote:
Terry wrote If you're only going to access each element of the file, then converting endian on access should be faster than swapping in place and then processing, without needing double the memory. Could you please give a specific example (preferably with code) that I could play with?
I was under the impression I already provided you with a use case in an earlier thread.
I'm looking for a specific application, (perhaps a specific video compression algorithm), that I can try. My previous test program read a large disk file, as you proposed. Now, I need something
Converting to endian on access certainly won't be faster than swap_in_place, as you cannot have a "zero cost" version. Additionally, in our scenarios the data gets accessed multiple times.
What is an example of one of these scenarios?
But just to re-iterate: 1) swap_in_place<>() can be zero cost in the case of no swapping, which cannot be said for the copying approach. I.e. it has a much better best case behaviour and the same cost for the worst case behaviour. 2) It is one of the safer ways of handling floating point numbers.
I disagree. I have demonstrated that... 1) endian-on-access can be zero cost in the native-case. 2) swapping in place is not any safer because the C++ type system cannot help to determine which portions of an object have been swapped, nor document the endian properties of a data structure. endian<big, double> can, and should, be defined to provided portable floating-point transfer and persistent storage. terry