A DSL for Implementing Math Functions

The blog post (a summary of a research paper) is targeted at PL researchers, and the mathematical notation would probably not add clarity.

> Yes, I can mentally substitute pi for pi but please put a pi on the page (it looks like a ... pi) ... Π

Uhm...Π is an upper case pi, which is the symbol for the product operator. For the symbol for the mathematical constant you want lower case pi, π.

That's an easy mistake to make on HN because HN asks for Verdana for the body of the page and for some unfathomable reason the designer of Verdana decided to make lower case pi just be a smaller version of upper case pi, so if you don't notice that you entered the product symbol instead of the symbol for the constant while in the comment editor there is a good chance you won't notice when you do a final proofread of the posted comment.

For reference here is the Greek alphabet, upper and lower case, in a code block which renders in something other than Verdana followed by the same thing not in a code block to show what Verdana does to Greek letters:

  Α α, Β β, Γ γ, Δ δ, Ε ε, Ζ ζ, Η η, Θ θ, Ι ι, Κ κ, Λ λ, Μ μ, Ν ν, Ξ ξ, Ο ο, Π π, Ρ ρ, Σ σ/ς, Τ τ, Υ υ, Φ φ, Χ χ, Ψ ψ, Ω ω

Α α, Β β, Γ γ, Δ δ, Ε ε, Ζ ζ, Η η, Θ θ, Ι ι, Κ κ, Λ λ, Μ μ, Ν ν, Ξ ξ, Ο ο, Π π, Ρ ρ, Σ σ/ς, Τ τ, Υ υ, Φ φ, Χ χ, Ψ ψ, Ω ω

Besides pi I'm not pleased by Verdana's lower case alpha, iota, nu, tau, chi, or psi but none of those are as annoying as its pi.

You write programs in the DSL in Python code; the actual executed library functions are in C.

Not immediately but it would be cool to integrate this with tools like flopoco that address that more directly.

In general it's hard to carry on projects after the main author leaves. The plan is to fold many of the capabilities into Herbie over time.