"The usage of a constant (like pi) that is one bit different..." That brings back memories of debugging a Fast Fourier Transform code that had a slightly misco

"The usage of a constant (like pi) that is one bit different..." That brings back memories of debugging a Fast Fourier Transform code that had a slightly miscoded version of pi. Someone typed it in from memory, to a dozen or so places (single precision), and got it slightly wrong. Talk about weird and hard to track down. Like being transported to the parallel universe where the cars ride on hexagons.