def _slope_triangle(origin, dx, dy, fc='0.8', **poly_kwargs):
    """Return Polygon representing slope.
          /|
         / | dy
        /__|
         dx
    """
    if 'ec' not in poly_kwargs and 'edgecolor' not in poly_kwargs:
        poly_kwargs['edgecolor'] = 'none'
    if 'fc' not in poly_kwargs and 'facecolor' not in poly_kwargs:
        poly_kwargs['facecolor'] = '0.8'
    verts = [np.asarray(origin)]
    verts.append(verts[0] + (dx, 0))
    verts.append(verts[0] + (dx, dy))
    return plt.Polygon(verts, **poly_kwargs)
dataset/ETHPy150Open tonysyu/mpltools/mpltools/annotation/_slopemarker.py/_slope_triangle/original