ax.step where parameter

[austin-hoover]

Description

In ax.step, the 'where' parameter doesn't do anything in proplot.

Steps to reproduce

import numpy as np
import proplot as pplt

x = np.linspace(-5.0, 5.0, 11)
y = np.exp(-0.5 * x**2)

fig, axes = pplt.subplots(nrows=3, figsize=(4.0, 3.0), spany=False)
for ax, where in zip(axes, ['pre', 'post', 'mid']):
    ax.step(x, y, where=where, color='black', alpha=0.2)
    ax.scatter(x, y, color='black', marker='.')
    ax.format(ylabel=where)

Expected behavior: The where parameter should shift the locations of the steps.

Actual behavior: The where parameter does not shift the locations of the steps.

Equivalent steps in matplotlib

import numpy as np
from matplotlib import pyplot as plt

x = np.linspace(-5.0, 5.0, 11)
y = np.exp(-0.5 * x**2)

fig, axes = plt.subplots(nrows=3, figsize=(4.0, 3.0), sharex=True)
for ax, where in zip(axes, ['pre', 'post', 'mid']):
    ax.step(x, y, where=where, color='black', alpha=0.2)
    ax.scatter(x, y, color='black', marker='.')
    ax.set_ylabel(where)

Proplot version

matplotlib=3.4.3 proplot=0.9.5

[pguenth]

can confirm using proplot=0.9.5.post301 and matplotlib=3.5.2

[AWSisco]

If you need an immediate solution to this using only Proplot, you can use the drawstyle argument with ax.plot instead to achieve the desired behavior.

import proplot as pplt
import numpy as np

x = np.linspace(-5.0, 5.0, 11)
y = np.exp(-0.5 * x**2)

fig, axes = pplt.subplots(nrows=3, figsize=(4.0, 3.0), spany=False)
for ax, drawstyle in zip(axes, ['steps', 'steps-post', 'steps-mid']):
    ax.plot(x, y, drawstyle=drawstyle, color='black', alpha=0.2)
    ax.scatter(x, y, color='black', marker='.')
    ax.format(ylabel=drawstyle, grid=False, ylocator=1)

proplot=0.9.5.post284 matplotlib=3.4.3

[lukelbd]

This was a very simple fix (https://github.com/proplot-dev/proplot/commit/0e18babf43193a44f038928f008e873ad95f271c). For some reason, a very long time ago, I added a "convenience" feature to step() converting where to this more complicated drawstyle='step-post' keyword arg... but I didn't realize step already had that conversion baked in / explicitly ignores drawstyle. So just removed the conversion. Result:

import numpy as np
import proplot as pplt

x = np.linspace(-5.0, 5.0, 11)
y = np.exp(-0.5 * x**2)

fig, axes = pplt.subplots(nrows=3, figsize=(4.0, 3.0), spany=False)
for ax, where in zip(axes, ['pre', 'post', 'mid']):
    ax.step(x, y, where=where, color='black', alpha=0.2)
    ax.scatter(x, y, color='black', marker='.')
    ax.format(ylabel=where)