power factor calculator

[ShoaibAbbasDev]

Describe your change:

• [:heavy_check_mark: ] Add an algorithm?
• [:heavy_check_mark: ] Fix a bug or typo in an existing algorithm?
• Add or change doctests? -- Note: Please avoid changing both code and tests in a single pull request.
• Documentation change?

Checklist:

• [:white_check_mark: ] I have read CONTRIBUTING.md.
• [ ✅ ] This pull request is all my own work -- I have not plagiarized.
• [:heavy_check_mark: ] I know that pull requests will not be merged if they fail the automated tests.
• [:heavy_check_mark: ] This PR only changes one algorithm file. To ease review, please open separate PRs for separate algorithms.
• [:heavy_check_mark: ] All new Python files are placed inside an existing directory.
• [:heavy_check_mark: ] All filenames are in all lowercase characters with no spaces or dashes.
• [:heavy_check_mark: ] All functions and variable names follow Python naming conventions.
• [:heavy_check_mark: ] All function parameters and return values are annotated with Python type hints.
• [:heavy_check_mark: ] All functions have doctests that pass the automated testing.
• [ ✔️ ] All new algorithms include at least one URL that points to Wikipedia or another similar explanation.
• [:heavy_check_mark: ] If this pull request resolves one or more open issues then the description above includes the issue number(s) with a closing keyword: "Fixes #ISSUE-NUMBER".

[priya-sundaram-dev]

Thanks for this, @ShoaibAbbasDev! The power-factor-correction maths look right. A few things needed before this can be merged, matching the repo's CONTRIBUTING conventions:

1. Type hints are required on every function. e.g. def calculate_apparent_power(voltage: float, current: float) -> float:, and likewise for the others.
2. Doctests are required — right now the module has none, so CI's doctest requirement isn't satisfied. Please add >>> examples to each function (including the error paths, e.g. calculate_power_factor(100, 0) raising ValueError), and a if __name__ == "__main__": import doctest; doctest.testmod() block.
3. The try/except TypeError -> raise ValueError wrapping is an anti-pattern here. With float type hints you don't need to guard against non-numbers, and calculate_reactive_power/calculate_correction_capacitance catch ValueError only to re-raise it with a "Calculation error:" prefix, which double-wraps and obscures the original message. I'd drop the try/except and validate inputs directly (if apparent_power == 0: raise ValueError(...)).

Also worth cross-checking against #9535 (shunt-capacitor PF correction) and #12356 so the electronics PF/transform modules don't overlap.