Since I got no answers I'm reposting I'm currently using multi_array to represent 3D matrices of doubles, I was wondering which would be the best use since the array has to hold a very large amount of data. I' currently testing whith a multi_array of 800x800x100 to hold double or pointers to double and I have memory problems. When I declare the multi_array whith pointers to doubles I can usually go up to 775x775x100 without problems but when I try the same thing with a multi_array of doubles I get a bad alloc error. My real needs for the moment are for a multi_array of 800x600x57 but I will need bigger storage capacity in the near future, what are your sugesstions. Is the multi_array a pointer itself? How is memory management handled? How can go beyond these limits? sebastien.fortier@ec.gc.ca