Improve print(mesh)

[prisae]

I think the current print-utility of meshes was made with small meshes in mind. It sort of explodes for big, stretched meshes:

I think something along these lines would be preferable (maybe as a rendered table in notebooks):

discretize.TensorMesh: 128 x 128 x 128 cells; 2,097,152 in total

    dir          min/max N            min/max h
    -----------------------------------------------------
     x:      -4176.3 / 4176.3;     25.0 / 143.0
     y:      -5902.6 / 5902.6;     50.0 / 160.8
     z:      -7151.7 / 7151.7;     20.0 / 355.8

[prisae]

Related, to some extent, to #21.

[banesullivan]

I could help implement a _repr_html_ method like what I did for vtki:

[prisae]

I think that would be great! But I think @lheagy and @rowanc1 and probably others of SimPEG have to chime in with their opinion, as it is their brainchild.

A few points:

• What happens if you are not in a notebook? Is there a plain text fallback?
• I think minimum cell-width in each distance would be useful.
• Maybe format the bounds as .1f instead of .3e

[banesullivan]

The _repr_html_ method is only ever used in an IPythonJupyter notebook environment. If you want a plain text representation to fall back on, then it can be implemented in the __repr__ method:

[prisae]

It would also go nicely along with the versions.

[prisae]

That is interesting. I never figured out, how to distinguish between a Notebook kernel and an IPython/Qt kernel. If you do the same in an IPython terminal, what will happen?

[prisae]

(The discussion around this problem is here: simpeg/simpeg#698).

[banesullivan]

As a developer, you don't have to do anything besides implement a method called _repr_html_ that returns a string of your HTML representation - Jupyter handles figuring out that it should be used. Ipython/Qt would call the __repr__ method by default

[banesullivan]

@prisae - if you want an HTML representation in notebooks and a plain text representation in IPython/Qt then simpll make class object for your versions info that implements the two __repr__ and _repr_html_ methods

[prisae]

I don't think it is that easy. See this screenshot from IPython:

[banesullivan]

What happens if you call repr(examples.load_rectilinear())?

[banesullivan]

Also here's something to test:

class Information(object):

    @property
    def n_cells(self):
        return 6

    @property
    def bounds(self):
        return (-1,1, -1,1, -1,1)

    def _get_attrs(self):
        """An internal helper for the representation methods"""
        attrs = []
        attrs.append(("N Cells", self.n_cells, "{}"))
        bds = self.bounds
        attrs.append(("X Bounds", (bds[0], bds[1]), "{:.3e}, {:.3e}"))
        attrs.append(("Y Bounds", (bds[2], bds[3]), "{:.3e}, {:.3e}"))
        attrs.append(("Z Bounds", (bds[4], bds[5]), "{:.3e}, {:.3e}"))
        return attrs


    def __repr__(self):
        fmt = "{} ({})\n".format(type(self).__name__, hex(id(self)))
        # now make a call on the object to get its attributes as a list of len 2 tuples
        row = "  {}:\t{}\n"
        for attr in self._get_attrs():
            try:
                fmt += row.format(attr[0], attr[2].format(*attr[1]))
            except:
                fmt += row.format(attr[0], attr[2].format(attr[1]))
        return fmt

    def _repr_html_(self):
        fmt = ""
        # HTML version
        fmt += "\n"
        fmt += "<table>\n"
        fmt += "<tr><th>{}</th><th>Information</th></tr>\n".format(type(self).__name__)
        row = "<tr><td>{}</td><td>{}</td></tr>\n"
        # now make a call on the object to get its attributes as a list of len 2 tuples
        for attr in self._get_attrs():
            try:
                fmt += row.format(attr[0], attr[2].format(*attr[1]))
            except:
                fmt += row.format(attr[0], attr[2].format(attr[1]))
        fmt += "</table>\n"
        fmt += "\n"
        return fmt


Information()

[prisae]

[banesullivan]

That's a bug on my part in vtki will fix now... try the basic Information class shared above

[prisae]

[banesullivan]

Went ahead and added in the bare bones for you @prisae: #143

[lheagy]

This is looking good and would be a great contribution!

Just a couple questions at this early stage:

• what do you mean be N in the first column? Would 'domain' be appropriate here?
• Visually, it might be more intuitive if the number of cells in each dimension is in the table rather than the first line

[rowanc1]

I think that it would be absolutely awesome to improve this print out. Starting down the road of useful (albeit at the start) static widgets is a really cool avenue to explore.

The print function was originally done by @dwfmarchant, back in 2014 or so! Probably in the first versions of the python implementation - lots of room for improvement. :)

[prisae]

Thanks for the help @bane, and for the feedback @lheagy, @rowanc1. I will look into this, hopefully next week or the week after.

[prisae]

This was fixed in #143 .