How to draw a correlation line in a matplotlib scatter plot?

Question

Below is the code for the scatter plot that I am trying to draw. I want to add a correlation line once the subplots are drawn. Although the code is running without an error, I can't see any line drawn in the plot. Any help will be much appreciated.

    fig, ax = plt.subplots(figsize=fs)
    for g in np.unique(group):
        ix = np.where(group == g)
        sc = ax.scatter(y[ix], dosage[ix], color = cdict[g], edgecolors='none')
    # Fit with polyfit
    b, m = polyfit(y, dosage, 1)
    ax.plot(y, b + m * y, '-')
    ax.set_xlabel('LT2', fontsize = 16)
    ax.set_ylabel('Log Dosage', fontsize = 16)
    # ax.legend(scatterpoints = 1, title='DILI Risk')

    # fig.colorbar(sc, label='Dosage/mg/day')
    path_dose = 'figure/reports/images/{}_hist_dose.png'.format(name_rep)
    data['hist_dosage'].append(path_dose)
    plt.savefig(path_dose)
    plt.close()

Below is the plot that I am getting.

Perhaps the documentation at https://matplotlib.org/api/_as_gen/matplotlib.pyplot.xcorr.html discussing xcorr within matplotlib would be useful — Reedinationer, Mar 12 '19 at 19:57
Without having access to your data and without seeing your plot we cannot tell you what’s going wrong — Sheldore, Mar 12 '19 at 20:04
It would be good to add a small (fictive) dataset to your question. — Ruthger Righart, Mar 12 '19 at 20:14

score 0 · Answer 1 · answered Mar 12 '19 at 21:00

0

Sorry guys, I had nans in my data. np.polyfit() did not work at the first place and therefore there was nothing to plot.

answered Mar 12 '19 at 21:00

Rohit Farmer

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How to draw a correlation line in a matplotlib scatter plot?

1 Answers1