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Because your floats deserve better than Base64.

Gem Version License: MIT

zfp brings LLNL's battle-hardened ZFP compression library to Ruby. ZFP was built by national-lab scientists to compress petabytes of floating-point simulation data without losing the ability to do science on it. Now it's in a Ruby gem.

Whether you're cramming ten years of OHLCV market data into Redis, shipping a million embedding vectors over the wire, or just deeply offended by how wasteful Array#pack("E*") is — this gem is for you.

What ZFP Actually Does

ZFP compresses n-dimensional arrays of floats, doubles, int32s, and int64s — up to 4 dimensions — using a floating-point-aware transform that exploits spatial correlation across array elements. Unlike general-purpose compressors, it understands the structure of numeric data.

Compression Modes at a Glance

Mode What it does Good for
:reversible Bit-exact lossless Audit trails, exact P&L, anything you'll diff
:fixed_rate Guaranteed bits-per-value Streaming, fixed-size storage slots
:fixed_precision Guaranteed significant bits Scientific reproducibility
:fixed_accuracy Guaranteed absolute error bound Financial data, ML embeddings, tolerance-bounded work

Five-Second Example

require "zfp"

prices = [174.21, 174.85, 173.40, 175.10, 176.33]  # ... 10,000 more

# Self-describing pack — no metadata bookkeeping required
packed   = Zfp.pack(prices, type: :double, shape: [prices.size], mode: :reversible)
restored = Zfp.unpack(packed)

prices == restored  # => true

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