I am trying to run a simulation with a large number of objects (mainly arrays and vectors). I am not sure where shall I define my objects: inside or outside of the main() function, like the following two structures:
I know there is a question about scope. But besides this question (which seems have no difference between these two structures here), is there any difference in terms of execution performance or security issue?
When are you creating fields/properties for specific classes and when you are not doing it but creating them inside just lets say straightaway inside some methods within that classes. I mean if i got class where inside i want to create instance of some other class and then pass this instance to another class - should i create a field for it within class i am doing this operation or not? I was always reading that you create field/properties when its belong to class itself. So if i want only to create some instance outside class i am working and pass it to other class and this is not exactly the part of this class shouldnt i create a field for it and just create it inside method?
I have a problem to read a large number of binary files, process them and store them under a new name. The program and routines go very well for 505 files. After reading 506 files, the program now refuses to read the next file. I have 16 Gb of memory and tried to close all other programs and restart the PC. it always stops after 506 files (512 files would be more understanding in a way...).
Here is my code. I have tried many things without success. This is only part of the loop that stops. The if test if (myfile.is_open() returns false by some reason. I can start the process again starting with the file that does not open and then it stops again after 506 files.
char * tfiBlock; ifstream myfile (OrigFilename, ios::in|ios::binary|ios::ate); if (myfile.is_open()) { int lengde = myfile.tellg(); tfiBlock = new char [lengde]; //static char memblock [size];
[Code] .....
Clean up procedure: delete[] tfiBlock;
Are there any limits to how many files that can be opened, or is it maybe someting to be set in the compiler?
I want to read a folder that contains large number of tif files. (say 1000 tif images) requirement is to read all files and store in a array/array pointer.
We have a program that sequentially processes a large number of files (currently about 700 expected to increase to about 1500). The program performs the same processing on each file (and doesn't involve any other file) which is io-bound and not cpu-bound. This process takes several hours and it is normally performed overnight.
I've refactored the program so that the processing for each file is done within its own thread (ie one thread created for the processing of one file). This gives rise to many hundreds of io-bound threads. This refactored program is working with no errors reported and has reduced the total processing time down to about 10 minutes.
Any problems that might arise having this number of threads (700 to 1500) created/running?
I have a piece of code which gets multiple objects to move randomly at a designated number of intervals. I want to create a function which calculates the distance between each pair of points after that number of steps. so the distance between object 1 and object 2, object 1 and object 3, ..., object 1 and object N. then object 2 and object 3, object 2 and object 4, ..., object 2 and object N. then then object 3 and object 4, object 3 and object 5, ..., object 3 and object N and so on until the distance between all the pairs of points have been calculated.
This has been bothering me for a while now, and I finally put together an example:
#include <iostream> #include <string> using namespace::std;
[Code]....
In the code above, the two classes hold pointers to each other, and that's fine but it doesn't seem right since C++ prefers to pass by reference. Yes, it can still do that (see testbox and testball) but even that seems odd to me because still you need to use pointer notation for the enclosed object. Am I the only one who feels this way, and should I just get over it? Or am I missing something that would allow an object to hold a reference?
In C++, the largest int value is 2147483647. So, an integer larger than this cannot be stored and processed as an integer. Similarly, if the sum or product of two positive integers is greater than 2147483647, the result will be incorrect. One way to store and manipulate large integers is to store each individual digit of the number in an array. Write a program that inputs two positive integers of, at most, 20 digits and outputs the sum of the numbers. If the sum of the numbers has more than 20 digits, output the sum with an appropriate message. Your program must, at least, contain a function to read and store a number into an array and another function to output the sum of the numbers. (Hint: Read numbers as strings and store the digits of the number in the reverse order.)
My code handles smaller numbers well enough, but I need the program to be able at least factor 100!.
#include <stdio.h> void factorialOutput(unsigned int &n, int fac[]); unsigned long long factorial(int n); int main(int argc, const char * argv[]) { unsigned int t = 0; int n[101];
when vpStatus is nonsense and unknown, the vaporPressure should not have a value; and if I calculate out a value for vaporPressure, the vpStatus can be set as known.
I am wondering if there is any set, pair or other structure can hold this two members together, so that when I change one's value, the other guy will also change accordingly.
