Fix issue 194

[codecov[bot]]

Codecov Report

Merging #297 (061e786) into fourier_coefficients (c1326d7) will decrease coverage by 0.05%. Report is 2 commits behind head on fourier_coefficients. The diff coverage is 60.00%.

@@                   Coverage Diff                    @@
##           fourier_coefficients     #297      +/-   ##
========================================================
- Coverage                 75.83%   75.78%   -0.05%     
========================================================
  Files                        86       86              
  Lines                      5391     5393       +2     
========================================================
- Hits                       4088     4087       -1     
- Misses                     1303     1306       +3     

Files	Coverage Δ
aurora/time_series/apodization_window.py	90.90% <ø> (ø)
aurora/time_series/time_axis_helpers.py	48.27% <ø> (ø)
aurora/transfer_function/plot/comparison_plots.py	100.00% <ø> (ø)
aurora/transfer_function/regression/m_estimator.py	89.36% <100.00%> (ø)
aurora/transfer_function/weights/edf_weights.py	97.26% <100.00%> (ø)
aurora/sandbox/mth5_helpers.py	0.00% <0.00%> (ø)

... and 1 file with indirect coverage changes

[kkappler]

All tests passing except for intermittent errors associated with external, web-based dependencies -- not sure how to fix this.
Namely, from lxml 3.9 push

XMLSyntaxError: Start tag expected, '<' not found, line 1, column 1

and from obspy 3.10 PR

UnicodeDecodeError: 'utf-8' codec can't decode byte 0x8b in position 1: invalid start byte