I've read from many that PL/V8 mathematic operations are generally faster than what you get with SQL functions and PL/pgsql functions. One area where I thought this speed would be really useful was for writing Map Algebra call-back functions. A PostGIS 2.1+ Map Algebra Callback function signature looks like: func_name(double precision[][][] value, integer[][] pos, text[] VARIADIC userargs)

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