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pythonmatplotliborientationcolorbar

Python- How to make colorbar orientation horizontal?


So I have a plot with a basemap, a colormesh on top, and a colorbar set to cbar. I want the colorbar orientation to be horizontal instead of vertical, but when I set orientation='horizontal' in the cbar=m.colorbar line after extend='max', I get the following error: "colorbar() got multiple values for keyword argument 'orientation'"

Someone on another question explained why this happens, but I honestly couldn't understand the answer or see an explanation of how to fix it. Can someone help? I tried using plt.colorbar instead, but for some reason that doesn't accept my tick settings.

Here's what my plot looked like before...

#Set cmap properties
bounds = np.array([0.1,0.2,0.5,1,2,3,4,6,9,13,20,30])
norm = colors.LogNorm(vmin=0.1,vmax=30) #creates logarithmic scale

#Create basemap
fig = plt.figure(figsize=(15.,10.))
m = Basemap(projection='cyl',llcrnrlat=-90,urcrnrlat=90,llcrnrlon=0,urcrnrlon=360.,lon_0=180.,resolution='c')
m.drawcoastlines(linewidth=1)
m.drawcountries(linewidth=1)
m.drawparallels(np.arange(-90,90,30.),linewidth=0.3)
m.drawmeridians(np.arange(-180.,180.,90.),linewidth=0.3)   
meshlon,meshlat = np.meshgrid(lon,lat)
x,y = m(meshlon,meshlat)

#Plot variables
trend = m.pcolormesh(x,y,lintrends_36,cmap='jet', norm=norm, shading='gouraud')

#Set plot properties
plt.tight_layout()
#Colorbar
cbar=m.colorbar(trend, size='3%',ticks=bounds,extend="max") #THIS LINE
cbar.set_label(label='Linear Trend (mm/day/decade)',size=30)
cbar.set_ticklabels(bounds)
#Titles & labels
plt.suptitle('Linear Trends of Precipitation (CanESM2)',fontsize=40,y=0.962)
plt.title('a) 1979-2014',fontsize=40)
plt.ylabel('Latitude',fontsize=30)
plt.show()

enter image description here

When orientation is attempted (all other code being the same)... enter image description here

And the map looks like this.

enter image description here


Solution

  • You need to use location="bottom"

    cbar=m.colorbar(trend, size='3%',ticks=bounds,extend="max",location="bottom")
    

    I got that from this example in the basemap documentation.

    enter image description here