Variable-Length Types

13.8 Variable-Length Types

Variable-Length types provide support for ragged arrays.

Simple example: ragged array

  types:
    float(*) row_of_floats;
  dimensions:
    m = 50;
  variables:
    row_of_floats ragged_array(m);

Has a name and a base type
Multiple variables may use same type
May be nested to create multidimensional variable-length types
Access to a variable-length value is atomic
- Length and values written or read together
- Can't know length until value is read
- In C/Fortran, library allocates memory for value

Nested example: in situ observations

Notes on netCDF-4 Variable-Length Types

Any base type may be used (including compound types and other variable-length types)
No associated shared dimension, unlike unlimited dimensions