Replace generics with pointers

[arteymix]

There's some work to do to fully implement pointer to GValue and its reciprocate. This endpoint is just a convenience because it's generally more efficient to work directly with pointers.

I also provide a pretty-print implementation based on GLib.Value.strdup_contents. It's nice as it considers matrix and vertices and print them vertically.

[arteymix]

Here's a preview for pretty prints:

For vertices:

dtype: gdouble, dsize: 8, shape: (6), mem: 48B
[1.000000
 1.000000
 1.000000
 1.000000
 1.000000
 1.000000]

For matrix:

dtype: gdouble, dsize: 8, shape: (5, 6), mem: 240B
[[0.000000, [0.000000, [0.000000, [0.000000, [0.000000,
  1.000000,  0.000000,  0.000000,  0.000000,  0.000000,
  1.000000,  0.000000,  0.000000,  0.000000,  0.000000,
  1.000000,  0.000000,  0.000000,  0.000000,  0.000000,
  1.000000,  0.000000,  0.000000,  0.000000,  0.000000,
  1.000000]  0.000000]  0.000000]  0.000000]  0.000000]]

For embedded matrix (ndim > 2)

dtype: gdouble, dsize: 8, shape: (4, 5, 6), mem: 960B
[
[[0.000000, [0.000000, [0.000000, [0.000000, [0.000000,
  1.000000,  0.000000,  0.000000,  0.000000,  0.000000,
  1.000000,  0.000000,  0.000000,  0.000000,  0.000000,
  1.000000,  0.000000,  0.000000,  0.000000,  0.000000,
  1.000000,  0.000000,  0.000000,  0.000000,  0.000000,
  1.000000]  0.000000]  0.000000]  0.000000]  0.000000]]
[[0.000000, [0.000000, [0.000000, [0.000000, [0.000000,
  0.000000,  0.000000,  0.000000,  0.000000,  0.000000,
  0.000000,  0.000000,  0.000000,  0.000000,  0.000000,
  0.000000,  0.000000,  0.000000,  0.000000,  0.000000,
  0.000000,  0.000000,  0.000000,  0.000000,  0.000000,
  0.000000]  0.000000]  0.000000]  0.000000]  0.000000]]
[[0.000000, [0.000000, [0.000000, [0.000000, [0.000000,
  0.000000,  0.000000,  0.000000,  0.000000,  0.000000,
  0.000000,  0.000000,  0.000000,  0.000000,  0.000000,
  0.000000,  0.000000,  0.000000,  0.000000,  0.000000,
  0.000000,  0.000000,  0.000000,  0.000000,  0.000000,
  0.000000]  0.000000]  0.000000]  0.000000]  0.000000]]
[[0.000000, [0.000000, [0.000000, [0.000000, [0.000000,
  0.000000,  0.000000,  0.000000,  0.000000,  0.000000,
  0.000000,  0.000000,  0.000000,  0.000000,  0.000000,
  0.000000,  0.000000,  0.000000,  0.000000,  0.000000,
  0.000000,  0.000000,  0.000000,  0.000000,  0.000000,
  0.000000]  0.000000]  0.000000]  0.000000]  0.000000]]]

It would be nice for embedded matrix to have a single line of [[[[ and use proper indentation.

[arteymix]

There's also a missing comma at the end of each matrix vertex.

[rainwoodman]

need a rebase or maybe I shall revert some changes in src/array.vala?

[arteymix]

@rainwoodman I'll deal with conflicts, I did [CCode (array_length = false)] twice.

[arteymix]

@rainwoodman I would really like that we do not prefix everything with Array, this library is basically revolving around that concept, so it get quite verbose to have StringArrayFormatter and the like.

[rainwoodman]

Yes it gets quite verbose!

I am guessing we will eventually wrap all array stuff in a subnamespace anyways, like Vast.Array, So let's remove Array prefix from class names.

[rainwoodman]

FYI: Some reading about matrix objects and nd array objects: https://docs.scipy.org/doc/numpy/reference/arrays.classes.html#matrix-objects

[arteymix]

Good I'll read some of it. I managed to understand strides since our last call and it's quite nice.

[rainwoodman]

I'll probably start drafting some prototype about the computing graph this week.

If you can, commit and merge often -- at this stage we don't really need to guarentee everything in the repo is runs correctly. (Just note broken parts with FIXME in the source).

[arteymix]

I already have something about introspection of functions here: https://github.com/rainwoodman/vast/tree/wip/arteymix/function-introspection.

It uses https://valadoc.org/gobject-introspection-1.0/GI.CallableInfo.html and the good thing is that it allow you to both introspect and call the function.

The following is what I try to accomplish:

var sin = new Function (GI.Repository.find_by_name ("Vast", "sin"));

sin.apply (in_array, ref out_array);

The Function wraps a CallableInfo and should extract all the information as well as the gradiant expression.

In the future, we'll want to have some description language (e.g. YAML) to get the graph.

[rainwoodman]

This is what I will try to accomplish:

var sin = new Operation(....);
var cos = new Operation(....);

var x = new Variable();
var r = new Variable();
sin.connect({x, r});
cos.connect({r, y})
var x0 = Array(...);
x.initialize(x0);
var y = y.evaluate();

Or maybe something similar. There needs to a stage where Array is bound to variables and Operation is bound to Function. The binding betwen operation and function could happen during

var sin = new Function (GI.Repository.find_by_name ("Vast", "sin"));

If Function class implementes the Operation interface too.

[rainwoodman]

Alternatively

var func = cos.nest(sin);
var x0 = Array(...);
var y = func.evaluate(x0);

But we need to save the temporaries during the evaluation.

[rainwoodman]

Shall we merge this as is? String can be dealt with later.

[arteymix]

Not yet, I'll make the tests work first (which is just a couple of changes) and we can finish all the set_value get_value` after.

[arteymix]

I'm merging the changes. We'll finish get_value and set_value later.