Python 我怎样才能反转 Plotly 的 Colorbar 的方向，以便顶部的小值和底部的大值

您可以反转色标，然后通过传递tickvals = [1, 1.1, ... 3.4]来硬编码记号，并使记号文本与之相反:ticktext = ['3.4', '3.3', ... '1'].这还需要您手动将文本" log(meters, 10)"添加到最上面的勾号.

我不知道为什么，但有一个奇怪的行为，在顶部和底部的记号和记号文本被切断-您可能需要调整一些记号的起始值和结束值.这可能与ColorBar的默认填充有关，也可能是我遗漏了什么.

import plotly.offline as off
import _tkinter

from matplotlib import pyplot as plt
from matplotlib import ticker
from matplotlib.dates import drange

import numpy as np
import pandas as pd

# use some sample data
df = pd.read_csv('https://raw.githubusercontent.com/plotly/datasets/master/2011_february_us_airport_traffic.csv')
lat_array, lon_array = df['lat'], df['long']
lat_min, lon_min = min(lat_array), min(lon_array)
lat_max, lon_max = max(lat_array), max(lon_array)
np.random.seed(42)
log_depth_array = np.random.uniform(0,3.3,size=len(df))

tickvals = np.arange(1-0.2,3.5,0.1)
ticktext = [str(f"{val:.1f}") for val in tickvals[::-1]]
ticktext[-3] = ticktext[-3] + " log(meters, 10)"

data = [ 
   dict(
        lat = lat_array,
        lon = lon_array,
        marker = dict(
            color = log_depth_array,
            colorscale = 'viridis_r',
            size = 6,
            colorbar = dict(
                title = 'Log Depth',
                # colorscale = "viridis_r",
                thickness = 10,
                titleside = "right",
                outlinecolor = "rgba(68, 68, 68, 0)",
                ticks = "outside",
                tickmode = "array",
                tickvals = tickvals,
                ticktext = ticktext,
                ticklen = 3,
            ),
        ),
        mode = 'markers',
        # text = mouseover_text,
        type = 'scattergeo'
    ) ]

layout = dict(
    geo = dict(
        showframe = True,
        framewidth = 25,
        scope = 'north america',
        showland = True,
        landcolor = "rgb(212, 212, 212)",
        showocean = True,
        oceancolor = "rgb(200, 255, 255)",
        subunitcolor = "rgb(0,0,0)",
        resolution = 50,
        projection = dict(
            type = 'robinson',
            rotation = dict(
                lon = -100
            )
        ),
        lonaxis = dict(
            showgrid = True,
            gridwidth = 0,
            range= [ lon_min-.4, lon_max+.4 ],
            dtick = 5
        ),
        lataxis = dict (
            showgrid = True,
            gridwidth = 0,
            range= [ lat_min-.4, lat_max+.4 ],
            dtick = 5
        )
    ),
)
fig = { 'data':data, 'layout':layout }
off.iplot(fig)