Running out of memory:

The VCODE interpreter  uses a fixed amount of memory for storing data. The default value depends on the configuration used (see Section 5.5), but is normally at least 1048576 ( ) 64-bit words. It can be changed with the command set memory_size n    (see Section 3.6).

If your program requires too much memory, you will get the following error ,

<Nesl> [0:1000000000];

Compiling..Writing..Loading..Running..
compacting vector memory...done
vinterp: ran out of vector memory.  Rerun using larger -m argument.
Reading..
Error at top level.  
Error: Error while running VCODE.

Before allocating more memory using set memory_size  (see Section 3.5), think about why you are running out of memory. Your algorithm might require more memory than your machine can possibly supply. Or your algorithm might have a bug and be recursing infinitely. In any case, the memory size probably should not be set to more than your total physical memory. So if you have 16 Megabytes on your workstation, don't set memory_size to anything more than 2097152 (2 Megawords). If you want to find out more about the memory system used by NESL and the meaning of the compacting vector memory message, see the paper on the implementation of NESL [2].