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pythonpandasmatplotliblegendlegend-properties

Change main plot legend label text


So far I have been able to label the subplots just fine but I'm having an issue with the main one.

Here's the relevant part of my code:

data_BS_P = data[channels[0]]
data_BS_R = data[channels[1]]
data_BS_Y = data[channels[2]]
plot_BS_P = data_BS_P.plot() #data_BS_P is a pandas dataframe
axBS = plot_BS_P.gca()
axBS.plot(data_BS_R, label='Roll')
axBS.plot(data_BS_Y, label='Yaw')
axBS.set_ylabel('Amplitude (urad)')
axBS.legend(loc='upper center', bbox_to_anchor=(0.5, 1.05), ncol=3,
            fancybox=True, shadow=True)
ml1 = MultipleLocator(10)
ml2 = MultipleLocator(3600)
axBS.yaxis.set_minor_locator(ml1)
axBS.xaxis.set_minor_locator(ml2)
plot_BS_P.save('L1-SUS-BS_M1_DAMP_PRY_INMON.jpg')

And this is what I have so far: enter image description here Notice the lengthy label for the blue line. I'd like that to be labeled as "Pitch" instead of the file name. In which line can I do that?


Solution

  • You need to gain access of the legend() object and use set_text() to change the text values, a simple example:

    plt.plot(range(10), label='Some very long label')
    plt.plot(range(1,11), label='Short label')
    L=plt.legend()
    L.get_texts()[0].set_text('make it short')
    plt.savefig('temp.png')
    

    enter image description here

    In your case, you are changing the first item in the legend, I am quite sure the 0 index in L.get_texts()[0] applies to your problem too.