Update base.py

[zakajd]

Closes #332

Proposed Changes

• [x] Fixed gradient map computation
• [ ] Updated all metrics to use proper kernel shapes (optional, function supports both variants now).

[codecov[bot]]

Codecov Report

Merging #333 (cc75629) into master (d04a848) will decrease coverage by 0.07%. The diff coverage is 71.42%.

@@            Coverage Diff             @@
##           master     #333      +/-   ##
==========================================
- Coverage   92.01%   91.94%   -0.07%     
==========================================
  Files          34       34              
  Lines        2491     2496       +5     
==========================================
+ Hits         2292     2295       +3     
- Misses        199      201       +2     

Flag	Coverage Δ
unittests	91.94% <71.42%> (-0.07%)	:arrow_down:

Flags with carried forward coverage won't be shown. Click here to find out more.

Impacted Files	Coverage Δ
piq/functional/base.py	88.37% <71.42%> (-3.74%)	:arrow_down:

[sonarcloud[bot]]

Kudos, SonarCloud Quality Gate passed!   

0 Bugs
0 Vulnerabilities
0 Security Hotspots
0 Code Smells

No Coverage information
0.0% Duplication