Turkish makam divides the octave into 53 equal commas (~22.64 cents each), not 12 semitones. The SymbTr corpus stores each note as an integer Koma53 value, anchored at C5 = 318.

midi = 72 + (koma − 318) × 12 / 53
fret = midi − open_string_midi

The fret is fractional because the MIDI value is — so "9.08" means press 9.08 semitones' worth up from the nut. Nothing is rounded. The neck above uses real logarithmic spacing (distance = scale × (1 − 2−fret/12)), so dots land exactly where your finger goes.