Generate an SVG sinusoid that gradually gets more rounded

svg_discrete_to_continuous.py

# SPDX-License-Identifier: 0BSD

from functools import partial
from itertools import chain, starmap, zip_longest

import numpy


def ascent(x):
    return [(x, 0), (1 - x, -1), (1, -1)]


def descent(x):
    return [(x, 0), (1 - x, 1), (1, 1)]


def squiggle(x1, x2):
    return chain([] if x1 is None else ascent(x1),
                 [] if x2 is None else descent(x2))


def groupwise(iterable, size):
    args = [iter(iterable)] * size
    return zip_longest(*args)


def space(n):
    return numpy.linspace(0, 1, n)


def pattern(n):
    return chain.from_iterable(starmap(squiggle, groupwise(space(n), 2)))


svg_template = """
<svg width="{width}" height="1" xmlns="http://www.w3.org/2000/svg">
  <path d="m 0,1 {curve}" fill="none" stroke="#f00" stroke-width="0.1" />
</svg>
""".strip()


def svg_curve(points):
    return " ".join(chain(["c"], map(lambda point: ",".join(map(str, point)), points)))


def svg_pattern(n):
    return svg_template.format(width=n, curve=svg_curve(pattern(n)))


if __name__ == "__main__":
    print(svg_pattern(31))  # fun prime