crystract 1.0.2

Performance Improvements

Massive Speedup in Symmetry Operations: Symmetry equations are now compiled into vectorized R functions once per structure, eliminating the severe CPU bottleneck caused by repeated string parsing (eval(parse())).
“Fast Fail” CIF Validation: Implemented high-speed pre-flight checks using raw C-level string matching. Invalid or severely malformed CIF files are now rejected in milliseconds, skipping unnecessary and expensive full-table regex scans.
Optimized Extraction: Replaced multiple heavy regular expression searches with highly optimized exact string matching during the mandatory data extraction phase.

Batch Processing Memory Exhaustion Resolved: Fixed a critical issue in analyze_cif_files() where large datasets would crash R by attempting to load all structures into system RAM simultaneously. CIF files are now dynamically read from disk strictly within their specified chunk/batch size, ensuring stable memory footprints when processing tens of thousands of files.

Refactored internal CIF extraction logic to robustly check for multiple alternative CIF tags when parsing chemical formulas, structure types, and space group names/numbers.
Updated README installation instructions to include options for both stable (CRAN) and development (GitHub) releases.
Improved the package vignette by updating Wyckoff filtering examples (from 4a to 4d) and adding a new section demonstrating how experimental errors are extracted from CIF loops and propagated through calculations.