<p>当我运行cmap定义时,<code>lcmap</code>有256个条目长,并且仅将第0个条目设置为新颜色在colorbar或几乎没有最低值的数据集中几乎看不到。我通过(1)将新颜色设置为绿色以获得最大的对比度,(2)将lcmap中最低的32个条目设置为新颜色,这很好。在basemap示例文件<a href="http://matplotlib.org/basemap/users/figures/plotsst.py" rel="nofollow noreferrer">plotsst.py</a>中,结果是:</p>
<p><a href="https://i.stack.imgur.com/Ns0IG.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/Ns0IG.png" alt="enter image description here"/></a></p>
<p>从插入此代码来替换定义<code>im1</code>的行:</p>
<pre><code>import palettable
cmap = palettable.colorbrewer.sequential.PuRd_9.mpl_colormap
lcmap = [cmap(i) for i in range(cmap.N)]
for i in range(32):
lcmap[i] = (0, .5, 0, 1.0)
cmap_green = cmap.from_list('0th entry green', lcmap, cmap.N)
im1 = m.pcolormesh(lons,lats,sst,shading='flat',cmap=cmap_green,latlon=True)
</code></pre>
<p><code>palettable.colorbrewer.sequential.PuRd_9</code>如预期的那样有9个值,但将其转换为<code>mpl_colormap</code>可以使其平滑到256。在</p>
<p>结合@Pablo Reyes的回答,插入的代码是</p>
^{pr2}$
<p>结果是</p>
<p><a href="https://i.stack.imgur.com/7hy6A.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/7hy6A.png" alt="enter image description here"/></a></p>
<p>给你!在</p>