HDFql Reference Manual v2.6.0

6.1.12VARTINYINT

The HDFql VARTINYINT data type stores values between -128 and 127 and occupies 1 byte in memory (per element). It represents the data type of an HDF5 (variable-length) H5T_NATIVE_CHAR dataset/attribute or of a result set that stores variable-length elements of this type (which can be retrieved using the HDFQL_CURSOR_GET_TINYINT and HDFQL_SUBCURSOR_GET_TINYINT functions when working with cursors). Depending on the programming language supported by HDFql, the VARTINYINT data type is represented by:

  • In C, the “char” data type.
  • In C++, the “char” data type.
  • In Java, the “ArrayList<Byte>” class.
  • In Python, the “int8” NumPy data type.
  • In C#, the “SByte” data type (or corresponding alias “sbyte”).
  • In Fortran, the “INTEGER(KIND = 1)” data type.
  • In R17, the “integer” data type.
  • In MATLAB, the “int8” data type.

Notes

  1. By design, R does not provide a data type that stores values between -128 and 127 using exactly 1 byte of memory. As a substitute, the R “integer” data type may be used, at the cost of increased memory usage (as it occupies 4 bytes of memory) and lower performance (as byte alignment must be performed by HDFql). ↩