This is correct commit to calculate mach meter angle:
https://github.com/danvac/Ikarus_Source/commit/76299deb07859895ec7a3ae42eab82c9a653d4c9
Input/Output values are bases on latest mainpanel_init.lua
MachIndicator = CreateGauge()
MachIndicator.arg_number = 179
MachIndicator.input = {0.5, 0.6, 0.7, 0.8, 0.9, 1.0, 1.1, 1.2, 1.3, 1.4, 1.5, 1.6, 1.7, 2.2}
MachIndicator.output = {1.0, 0.929, 0.871, 0.816, 0.765, 0.727, 0.683, 0.643, 0.611, 0.582, 0.551, 0.525, 0.5, 0.4}
MachIndicator.controller = controllers.MachIndicator