Notation as a tool for thought: Wavelets in J
Summary
Scott Locklin's post documents writing a wavelet toolbox in the J language, comparing a C reference implementation with a J/FI approach, and exploring tacit programming concepts. It explains the discrete wavelet transform (DWT) as a pyramid algorithm, details how J handles verbs, dyad defines, adverbs, and the FFI, and provides code samples for level-by-level DWT, inverse DWT, and multi-level reconstruction. The piece also reflects on notation as a tool of thought and references Iverson's ideas.