Configuration management using files (YAML, JSON, INI, TXT),
  JSON strings, and command line arguments. Command line arguments
  can be used to override configuration. Period-separated command line
  flags are parsed as hierarchical lists. Environment variables, R global variables,
  and configuration values can be substituted.

Solve some conic related problems (intersection of conics with lines and conics, arc length of an ellipse, polar lines, etc.).

Convert text into target classifications (e.g., ISO 3166-1) using a
    JSON mapping with regular expressions. Provides helpers to return the full
    mapping and associated metadata.

Researchers across disciplines often face biased regression
    model estimates due to endogenous regressors correlated with the error
    term. Traditional solutions require instrumental variables (IVs), which
    are often difficult to find and validate. This package provides
    flexible, alternative IV-free methods using copulas, as described in
    the practical guide to endogeneity correction using copulas (Yi Qian,
    Tony Koschmann, and Hui Xie 2025) <doi:10.1177/00222429251410844>. The
    current version implements the two-stage copula endogeneity correction
    (2sCOPE) method to fit models with continuous endogenous regressors and
    both continuous and discrete exogenous regressors, as described in Fan
    Yang, Yi Qian, and Hui Xie (2024)
    <doi:10.1177/00222437241296453>. Using this method, users can address
    regressor endogeneity problems in nonexperimental data without
    requiring IVs.

A configuration-driven framework for running domain-level data quality checks and consolidating findings into structured Excel reports with role-based feedback routing.
    It supports trial-level and study-level checks across multiple data domains.
    Reports are routed to separate feedback channels for Data Management (DM), Medical Writing (MW), Study Data Tabulation Model (SDTM) programmers, and Analysis Data Model (ADaM) programmers, as well as other relevant data roles.
    Reviewer responses are incorporated automatically on re-run.