我想使用颜色映射"viridis" (http://bids.github.io/colormap/),我不会更新到开发版本1.5。因此,我从https://github.com/BIDS/colormap下载了colormaps.py
。不幸的是,我不能让它工作。我是这样做的:
import matplotlib.pyplot as plt
import matplotlib.image as mpimg
import numpy as np
import colormaps as cmaps
img=mpimg.imread('stinkbug.png')
lum_img = np.flipud(img[:,:,0])
plt.set_cmap(cmaps.viridis)
imgplot = plt.pcolormesh(lum_img)
这给了我一个ValueError
,回溯以
结尾ValueError: Colormap viridis不可识别。可能的值有:光谱、夏季、冷暖、…
(然后是原始安装的颜色映射的完整列表)
对如何解决这个问题有什么想法吗?
要使用set_cmap
将viridis
设置为您的颜色映射,您必须首先注册它:
import colormaps as cmaps
plt.register_cmap(name='viridis', cmap=cmaps.viridis)
plt.set_cmap(cmaps.viridis)
img=mpimg.imread('stinkbug.png')
lum_img = np.flipud(img[:,:,0])
imgplot = plt.pcolormesh(lum_img)
您可以直接在pcolormesh
调用
cmap
,而不是使用需要matplotlib.colors.Colormap
实例的set_cmap
。(cmaps.viridis
是matplotlib.colors.ListedColormap
)
import matplotlib.pyplot as plt
import matplotlib.image as mpimg
import numpy as np
import colormaps as cmaps
img=mpimg.imread('stinkbug.png')
lum_img = np.flipud(img[:,:,0])
imgplot = plt.pcolormesh(lum_img, cmap=cmaps.viridis)
我所做的就是复制
_viridis_data = [[0.267004, 0.004874, 0.329415],
[0.268510, 0.009605, 0.335427],
[0.269944, 0.014625, 0.341379],
:
[0.983868, 0.904867, 0.136897],
[0.993248, 0.906157, 0.143936]]
从https://github.com/BIDS/colormap/blob/master/colormaps.py 并添加:
from matplotlib.colors import ListedColormap
viridis = ListedColormap(_viridis_data, name='viridis')
plt.register_cmap(name='viridis', cmap=viridis)
plt.set_cmap(viridis)
从这里下载colormaps.py,然后:
import os,sys
scriptpath = "/Your downloading path/colormap-master/"
sys.path.append(os.path.abspath(scriptpath))
import colormaps as cmaps
完成了!