ceify

A small command-line utility for converting spectrophotometer output files into a format compatible with CompleteEASE.

Motivation

This tool was created out of frustration with repeatedly converting spectral data files using Excel or small Python scripts. The process was slow, error-prone, and inconvenient for routine work.

ceify is intended to be a simple, reliable, drop-in replacement that performs the conversion directly from the command line with no external dependencies.

What it does

ceify reads raw spectrophotometer output files and converts them into text files formatted for CompleteEASE.

Currently supported input formats:

• PerkinElmer Lambda 1050 (.asc, .txt-like)
• Agilent Cary (.csv)

The program automatically detects the input format based on file extension and produces one or more output files in the same directory.

Output format

Generated files follow the CompleteEASE-compatible structure:

Spectroscopic Intensity Data
uT or uR
nm
<wavelength> <value>

• Wavelengths are written in nanometers
• Values are normalized to the range [0, 1]
• Output files are suffixed with:
  • _uT.txt for transmission
  • _uR.txt for reflection

Usage

ceify <input_file>

Example:

ceify transmission_spectrum.asc

ceify measurement.csv

Output files are written to the same directory as the input file.

Features

• Single static binary, no dependencies
• Works on Linux, macOS, and Windows
• Automatic format detection (case-insensitive extensions)
• Strict validation of input data
• Clear error messages with line numbers
• Handles both transmission and reflection data
• Simple and predictable output format

Behavior

• Files are parsed in a single pass
• Input data is validated strictly:
  • Missing %T / %R markers (Lambda 1050) result in an error
  • Malformed lines (wrong number of columns) result in an error
  • Invalid numeric values result in an error with line number
• Leading/trailing whitespace in values is ignored
• Empty or invalid datasets are rejected

Implementation

The program is written in Rust and uses only the standard library.

Structure

• SpectralData represents a single dataset (wavelength + values + type)
• Converter trait defines a common interface for parsers
• Separate implementations exist for each supported instrument:
  • Lambda1050
  • Cary
• Output writing is shared across all formats

Parsing

• Lambda 1050:

  • Detects %T or %R from a fixed header line
  • Reads spectral data starting from a fixed offset
  • Validates column count and numeric values

• Cary:

  • Parses CSV rows without external libraries
  • Extracts reflection and transmission data simultaneously
  • Validates structure and numeric values for each row

Output

• Files are written using buffered I/O
• Data is formatted with fixed precision
• Output filenames are derived from the input filename

Output files will be created in the same directory as the input file.

Building

Requires Rust (1.90+ should work, tested with newer versions).

cargo build --release

Binary will be located at:

target/release/ceify

Limitations

• Assumes consistent file structure from supported instruments
• CSV parsing is simplified (no quoted field handling)
• No batch processing

License

GPL-3.0