Fortran 90 lets you define deferred shape arrays and pointers. The actual bounds of a deferred shape array are not determined until the array is allocated, the pointer is assigned, or, in the case of an assumed shape argument to a subroutine, the subroutine is called.

The following example shows the type of a deferred shape array of real data with no defined lower or upper bounds:

Here is the unallocated array displayed in the Data View:

As you run the program, the array is allocated at line 303 below. Note that the type has been modified in the Data View.