TypeError: 'float' object cannot be interpreted as an index

[hendrikschilling]

Traceback (most recent call last):
File "plot_metric_overview.py", line 51, in
main()
File "plot_metric_overview.py", line 47, in main
metric_overviews.plot_general_overview(algorithms+meta_algorithms, scenes, metrics)
File "/data/lf_data/synthetic/toolkit/source/toolkit/evaluations/metric_overviews.py", line 193, in plot_general_overview
colorbar_bins=metric.colorbar_bins, fontsize=fs)
File "/data/lf_data/synthetic/toolkit/source/toolkit/utils/plotting.py", line 104, in add_colorbar
plt.imshow(np.ones((height*scale, img_width)), alpha=0)
File "/usr/lib/python2.7/site-packages/numpy/core/numeric.py", line 192, in ones
a = empty(shape, dtype, order)
TypeError: 'float' object cannot be interpreted as an index