svg.py

#This module is taken from the Dask project and can be found here:
#https://github.com/dask/dask/blob/master/dask/array/svg.py
#It has been slightly modified to allow for the representation of numpy arrays.
#Here is the accompanying license:

'''
Copyright (c) 2014-2018, Anaconda, Inc. and contributors
All rights reserved.

Redistribution and use in source and binary forms, with or without modification,
are permitted provided that the following conditions are met:

Redistributions of source code must retain the above copyright notice,
this list of conditions and the following disclaimer.

Redistributions in binary form must reproduce the above copyright notice,
this list of conditions and the following disclaimer in the documentation
and/or other materials provided with the distribution.

Neither the name of Anaconda nor the names of any contributors may be used to
endorse or promote products derived from this software without specific prior
written permission.

THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF
THE POSSIBILITY OF SUCH DAMAGE.
'''

import math
import re

import numpy as np
from IPython.display import HTML

def svg(chunks, size=200, **kwargs):
    """ Convert chunks from Dask Array into an SVG Image

    Parameters
    ----------
    chunks: tuple
    size: int
        Rough size of the image

    Returns
    -------
    text: An svg string depicting the array as a grid of chunks
    """
    shape = tuple(map(sum, chunks))
    if np.isnan(shape).any():  # don't support unknown sizes
        raise NotImplementedError(
            "Can't generate SVG with unknown chunk sizes.\n\n"
            " A possible solution is with x.compute_chunk_sizes()"
        )
    if not all(shape):
        raise NotImplementedError("Can't generate SVG with 0-length dimensions")
    if len(chunks) == 0:
        raise NotImplementedError("Can't generate SVG with 0 dimensions")
    if len(chunks) == 1:
        return svg_1d(chunks, size=size, **kwargs)
    elif len(chunks) == 2:
        return svg_2d(chunks, size=size, **kwargs)
    elif len(chunks) == 3:
        return svg_3d(chunks, size=size, **kwargs)
    else:
        return svg_nd(chunks, size=size, **kwargs)


text_style = 'font-size="1.0rem" font-weight="100" text-anchor="middle"'


def svg_2d(chunks, offset=(0, 0), skew=(0, 0), size=200, sizes=None):
    shape = tuple(map(sum, chunks))
    sizes = sizes or draw_sizes(shape, size=size)
    y, x = grid_points(chunks, sizes)

    lines, (min_x, max_x, min_y, max_y) = svg_grid(x, y, offset=offset, skew=skew)

    header = (
        '<svg width="%d" height="%d" style="stroke:rgb(0,0,0);stroke-width:1" >\n'
        % (max_x + 50, max_y + 50)
    )
    footer = "\n</svg>"

    if shape[0] >= 100:
        rotate = -90
    else:
        rotate = 0

    text = [
        "",
        "  <!-- Text -->",
        '  <text x="%f" y="%f" %s >%d</text>'
        % (max_x / 2, max_y + 20, text_style, shape[1]),
        '  <text x="%f" y="%f" %s transform="rotate(%d,%f,%f)">%d</text>'
        % (max_x + 20, max_y / 2, text_style, rotate, max_x + 20, max_y / 2, shape[0]),
    ]

    return header + "\n".join(lines + text) + footer


def svg_3d(chunks, size=200, sizes=None, offset=(0, 0)):
    shape = tuple(map(sum, chunks))
    sizes = sizes or draw_sizes(shape, size=size)
    x, y, z = grid_points(chunks, sizes)
    ox, oy = offset

    xy, (mnx, mxx, mny, mxy) = svg_grid(
        x / 1.7, y, offset=(ox + 10, oy + 0), skew=(1, 0)
    )

    zx, (_, _, _, max_x) = svg_grid(z, x / 1.7, offset=(ox + 10, oy + 0), skew=(0, 1))
    zy, (min_z, max_z, min_y, max_y) = svg_grid(
        z, y, offset=(ox + max_x + 10, oy + max_x), skew=(0, 0)
    )

    header = (
        '<svg width="%d" height="%d" style="stroke:rgb(0,0,0);stroke-width:1" >\n'
        % (max_z + 50, max_y + 50)
    )
    footer = "\n</svg>"

    if shape[1] >= 100:
        rotate = -90
    else:
        rotate = 0

    text = [
        "",
        "  <!-- Text -->",
        '  <text x="%f" y="%f" %s >%d</text>'
        % ((min_z + max_z) / 2, max_y + 20, text_style, shape[2]),
        '  <text x="%f" y="%f" %s transform="rotate(%d,%f,%f)">%d</text>'
        % (
            max_z + 20,
            (min_y + max_y) / 2,
            text_style,
            rotate,
            max_z + 20,
            (min_y + max_y) / 2,
            shape[1],
        ),
        '  <text x="%f" y="%f" %s transform="rotate(45,%f,%f)">%d</text>'
        % (
            (mnx + mxx) / 2 - 10,
            mxy - (mxx - mnx) / 2 + 20,
            text_style,
            (mnx + mxx) / 2 - 10,
            mxy - (mxx - mnx) / 2 + 20,
            shape[0],
        ),
    ]

    return header + "\n".join(xy + zx + zy + text) + footer


def svg_nd(chunks, size=200):
    if len(chunks) % 3 == 1:
        chunks = ((1,),) + chunks
    shape = tuple(map(sum, chunks))
    sizes = draw_sizes(shape, size=size)

    chunks2 = chunks
    sizes2 = sizes
    out = []
    left = 0
    total_height = 0
    while chunks2:
        n = len(chunks2) % 3 or 3
        o = svg(chunks2[:n], sizes=sizes2[:n], offset=(left, 0))
        chunks2 = chunks2[n:]
        sizes2 = sizes2[n:]

        lines = o.split("\n")
        header = lines[0]
        height = float(re.search(r'height="(\d*\.?\d*)"', header).groups()[0])
        total_height = max(total_height, height)
        width = float(re.search(r'width="(\d*\.?\d*)"', header).groups()[0])
        left += width + 10
        o = "\n".join(lines[1:-1])  # remove header and footer

        out.append(o)

    header = (
        '<svg width="%d" height="%d" style="stroke:rgb(0,0,0);stroke-width:1" >\n'
        % (left, total_height)
    )
    footer = "\n</svg>"
    return header + "\n\n".join(out) + footer


def svg_lines(x1, y1, x2, y2):
    """ Convert points into lines of text for an SVG plot

    Examples
    --------
    >>> svg_lines([0, 1], [0, 0], [10, 11], [1, 1])  # doctest: +NORMALIZE_WHITESPACE
    ['  <line x1="0" y1="0" x2="10" y2="1" style="stroke-width:2" />',
     '  <line x1="1" y1="0" x2="11" y2="1" style="stroke-width:2" />']
    """
    n = len(x1)
    lines = [
        '  <line x1="%d" y1="%d" x2="%d" y2="%d" />' % (x1[i], y1[i], x2[i], y2[i])
        for i in range(n)
    ]

    lines[0] = lines[0].replace(" /", ' style="stroke-width:2" /')
    lines[-1] = lines[-1].replace(" /", ' style="stroke-width:2" /')
    return lines


def svg_grid(x, y, offset=(0, 0), skew=(0, 0)):
    """ Create lines of SVG text that show a grid

    Parameters
    ----------
    x: numpy.ndarray
    y: numpy.ndarray
    offset: tuple
        translational displacement of the grid in SVG coordinates
    skew: tuple
    """
    # Horizontal lines
    x1 = np.zeros_like(y) + offset[0]
    y1 = y + offset[1]
    x2 = np.full_like(y, x[-1]) + offset[0]
    y2 = y + offset[1]

    if skew[0]:
        y2 += x.max() * skew[0]
    if skew[1]:
        x1 += skew[1] * y
        x2 += skew[1] * y

    min_x = min(x1.min(), x2.min())
    min_y = min(y1.min(), y2.min())
    max_x = max(x1.max(), x2.max())
    max_y = max(y1.max(), y2.max())

    h_lines = ["", "  <!-- Horizontal lines -->"] + svg_lines(x1, y1, x2, y2)

    # Vertical lines
    x1 = x + offset[0]
    y1 = np.zeros_like(x) + offset[1]
    x2 = x + offset[0]
    y2 = np.full_like(x, y[-1]) + offset[1]

    if skew[0]:
        y1 += skew[0] * x
        y2 += skew[0] * x
    if skew[1]:
        x2 += skew[1] * y.max()

    v_lines = ["", "  <!-- Vertical lines -->"] + svg_lines(x1, y1, x2, y2)

    rect = [
        "",
        "  <!-- Colored Rectangle -->",
        '  <polygon points="%f,%f %f,%f %f,%f %f,%f" style="fill:#ECB172A0;stroke-width:0"/>'
        % (x1[0], y1[0], x1[-1], y1[-1], x2[-1], y2[-1], x2[0], y2[0]),
    ]

    return h_lines + v_lines + rect, (min_x, max_x, min_y, max_y)


def svg_1d(chunks, sizes=None, **kwargs):
    return svg_2d(((1,),) + chunks, **kwargs)


def grid_points(chunks, sizes):
    cumchunks = [np.cumsum((0,) + c) for c in chunks]
    points = [x * size / x[-1] for x, size in zip(cumchunks, sizes)]
    return points


def draw_sizes(shape, size=200):
    """ Get size in pixels for all dimensions """
    mx = max(shape)
    ratios = [mx / max(0.1, d) for d in shape]
    ratios = [ratio_response(r) for r in ratios]
    return tuple(size / r for r in ratios)


def ratio_response(x):
    """ How we display actual size ratios

    Common ratios in sizes span several orders of magnitude,
    which is hard for us to perceive.

    We keep ratios in the 1-3 range accurate, and then apply a logarithm to
    values up until about 100 or so, at which point we stop scaling.
    """
    if x < math.e:
        return x
    elif x <= 100:
        return math.log(x + 12.4)  # f(e) == e
    else:
        return math.log(100 + 12.4)
    
def numpy_to_svg(array):
    
    return HTML(svg(tuple((tuple(np.ones(x)) for x in array.shape))))