Numerical Calculations in Clifford Algebra

27Descriptions

This chapter contains detailed descriptions of the application programmer interfaces (APIs) in alphabetical order. For a list of the interfaces organised in terms of function with cross references to these pages, see Chapter 26. For a quick reference, see Section 27.5.

27.1 Arguments

The functional type of the arguments specified in the interfaces to the individual sub‐routines is identified in the descriptions by single letter codes as listed in Table 27.1.

Arguments of type ‘i’ (input) are set by the user to some value which is used to control the behaviour of the sub‐routine. Arguments of type ‘o’ (output) are used by the sub‐routine to pass some result back to the user. Some arguments have both types input and output. In this case, the values set up by the user are modified by the sub‐routine.

Arguments of type ‘r’ (recycled) are numbers which are in some way consumed by the sub‐routine and no longer valid on exit from the sub‐routine. An example is the sub‐routine addto_number() which uses the memory associated with the first argument as the basis on which to construct the result, since many of the components are already in place. This is faster than constructing a whole new number.

Arguments of type ‘d’ (disposed) are either recycled or not, according to the value of the flag set by the user in another argument. This extra argument, the disposal flag ‘d’, is found as the last in the list of arguments. It indicates which of the previous arguments should ...