MCNP I/O

Parse MCNP material cards, xsdir, meshtal, MCTAL, and WWINP files.

The mcnp-io crate reads and writes several MCNP-family file formats. On this page we can only work from text strings, which is still enough to inspect decks and convert small files.

Supported formats

• Material cards — m1 92235 -0.04 92238 -0.96 style definitions, including comment metadata.
• xsdir — cross-section directory with AWR table and continuous-energy entries.
• meshtal — fmesh tally output with structured mesh results and relative errors.
• MCTAL — header, standard tally bodies (f/d/u/s/m/c/e/t bins plus vals pairs), and kcode cycles.
• WWINP — Cartesian weight-window lower bounds.

Try it

Select a parser and paste a file snippet. The demo returns a JSON summary that you can inspect without leaving the page. For meshtal files, load the sample and view the tally as a z-slice heatmap; parsed xsdir tables are summarised as a histogram by element, with companion views of table counts by library suffix and the AWR distribution. For MCTAL files, load the sample to see the header plus a per-tally table of pair counts and totals.

See also

• Full-deck editing lives in the deck-editor demo.
• Tutorial: Parse MCNP output
• Crate docs: crates/mcnp-io/src/lib.rs