Convert docstrings to numpy-style format

[Copilot]

• Explore repository structure to understand existing docstrings
• Identify modules and classes that need numpy-style docstrings
• Add numpy-style docstrings to pypfopt modules:
  • exceptions.py
  • objective_functions.py
  • expected_returns.py
  • discrete_allocation.py
  • base_optimizer.py
  • risk_models.py
  • hierarchical_portfolio.py
  • efficient_frontier/efficient_frontier.py
  • black_litterman.py
  • cla.py
  • plotting.py
  • efficient_frontier/efficient_cvar.py
  • efficient_frontier/efficient_semivariance.py
  • efficient_frontier/efficient_cdar.py
• Add numpy-style docstrings to tests/utilities_for_tests.py
• Verify tests still pass (284 passed)
• Run code review and address feedback
• Run CodeQL security analysis (no issues found)

Original prompt

---

This section details on the original issue you should resolve

<issue_title>Docstrings for everybody</issue_title>
<issue_description>Create docstrings in numpy-style for all attributes and methods in pyfopt and tests. Complete with examples</issue_description>

Comments on the Issue (you are @copilot in this section)

• Fixes Docstrings for everybody #12

---

💬 We'd love your input! Share your thoughts on Copilot coding agent in our 2 minute survey.

[coderabbitai]

Important

Review skipped

Bot user detected.

To trigger a single review, invoke the @coderabbitai review command.

You can disable this status message by setting the reviews.review_status to false in the CodeRabbit configuration file.

---

_{Comment @coderabbitai help to get the list of available commands and usage tips.}

[tschm]

@copilot also add missing docstrings in pyfopt and tests

[tschm]

copilot: fix broken code-quality issue

[Copilot]

@copilot also add missing docstrings in pyfopt and tests

Added numpy-style docstrings to all pypfopt modules and tests/utilities_for_tests.py in commits 25def59 through 8295f5d.

Updated modules:

• black_litterman.py, cla.py, plotting.py
• efficient_frontier/efficient_cvar.py, efficient_semivariance.py, efficient_cdar.py
• tests/utilities_for_tests.py

All 284 tests pass.