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[mhostetter]

• Fixes Add sdr.plot.stem() #391
• Fixes Add sdr.plot.dft #19
• Fixes Add sdr.plot.dtft() #394
• Fixes Standardize capitalization in figures #390
• Fixes Add stem plots to impulse/step responses #393

[codecov-commenter]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 79.59%. Comparing base (bfbc148) to head (e85bc7d).
Report is 1 commits behind head on release/0.0.x.

Additional details and impacted files

@@              Coverage Diff               @@
##           release/0.0.x     #395   +/-   ##
==============================================
  Coverage          79.59%   79.59%           
==============================================
  Files                 63       63           
  Lines               3931     3931           
==============================================
  Hits                3129     3129           
  Misses               802      802           

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