当matplotlib中的值"换行"时,防止绘图连接

Question

我正在为行星绘制正确的提升 星历,它们具有周期性的特性:它们达到最大值24,然后再从0开始.当我使用matplotlib绘制这些时,从24到0的"跳跃"是加入,以便我在我的身材上运行水平线:

我怎样才能消除这些线？matplotlib中是否有方法,或者可能是在跳转发生点之间拆分列表的方法.

---

生成上图的代码:

from __future__ import division

import ephem
import matplotlib
import matplotlib.pyplot
import math

fig, ax = matplotlib.pyplot.subplots()

ax.set(xlim=[0, 24])
ax.set(ylim=[min(date_range), max(date_range)])

ax.plot([12*ep.ra/math.pi for ep in [ephem.Jupiter(base_date + d) for d in date_range]], date_range,
        ls='-', color='g', lw=2)
ax.plot([12*ep.ra/math.pi for ep in [ephem.Venus(base_date + d) for d in date_range]], date_range,
        ls='-', color='r', lw=1)
ax.plot([12*ep.ra/math.pi for ep in [ephem.Sun(base_date + d) for d in date_range]], date_range,
        ls='-', color='y', lw=3)

Answer 1

这是一个生成器函数,用于查找"包装"数据的连续区域:

import numpy as np

def unlink_wrap(dat, lims=[-np.pi, np.pi], thresh = 0.95):
    """
    Iterate over contiguous regions of `dat` (i.e. where it does not
    jump from near one limit to the other).

    This function returns an iterator object that yields slice
    objects, which index the contiguous portions of `dat`.

    This function implicitly assumes that all points in `dat` fall
    within `lims`.

    """
    jump = np.nonzero(np.abs(np.diff(dat)) > ((lims[1] - lims[0]) * thresh))[0]
    lasti = 0
    for ind in jump:
        yield slice(lasti, ind + 1)
        lasti = ind + 1
    yield slice(lasti, len(dat))

一个示例用法是,

x = np.arange(0, 100, .1)
y = x.copy()

lims = [0, 24]

x = (x % lims[1])

fig, ax = matplotlib.pyplot.subplots()

for slc in unlink_wrap(x, lims):
    ax.plot(x[slc], y[slc], 'b-', linewidth=2)

ax.plot(x, y, 'r-', zorder=-10)
ax.set_xlim(lims)

这给出了下图.请注意,蓝线(使用中unlink_wrap)被破坏,标准绘制的红线显示为参考.