GAViewer 0.43 manual (.pdf)

Chapter 4
The Programming Language
and the Console
GAViewer contains a small internal programming language. It is basically a C-
like language, with features like functions and conditional control structures,
global and local scopes. It has a very limited set of types (3D Euclidean multivectors,
4D homogeneous multivectors, 5D conformal multivectors). These
types can be automatically coerced. Functions can be overloaded. There is limited
support for arrays. Dynamic statements allow for quite amazing flexibility.
Dynamic statements depend on the variables used to evaluate them. Every time
such a variable changes, the dynamic statement is reevaluated.
The programming language can be used on the console, and in .g files.
These files typically contain functions and batches.
A large number of built in functions are provided too handle all kinds of
typical GA operations.
4.1 Comma, semicolon and space
As in Matlab, the symbol used to terminate a statement determines if the result
is shown on the console/view window. Typing
>> a = e1,
will pop up a vector in the view window and show you the coordinates of a on
the console. On the other hand, typing
>> a = e1;
hides the vector and does not print its coordinates. The multivector a still exists,
but it is simply not shown. You can use the menu view→hide→show
hidden object to make it appear again. Using no symbol to end a statement is
equivalent to a comma:
>> a = e1
This will again pop up a vector in the view window and show you the coordinates
of a on the console. In .g files, you must always terminate all statements
with either a semicolon or a comma.
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