int sym_get_num_elements(sym_environment *env, int *numelems)
This routine is used to get the number of non-zero entries of the constraint matrix of the current problem.
| sym_environment *env | IN | Pointer to the SYMPHONY environment. | 
| int *numelems | OUT | Pointer to an integer indicating the number of non-zero elements. | 
| FUNCTION_TERMINATED_ABNORMALLY | Function invoked unsuccessfully. | 
| FUNCTION_TERMINATED_NORMALLY | Function invoked successfully. |