Compass COMPASS_DIA_X parameter -?

Hi, sorry, i for some reason cannot find what is the exact meaning/purpose of the COMPASS_DIA_X , COMPASS_DIA_Y, COMPASS_DIA_Z params?
Was there an article somewhere on what is the ‘soft-iron calibration matrix’ is? Is it something new?

so, no one knows what are those new options with a ‘soft-iron calibration matrix’ descriptions? no reference to that stuff at all? i hate to go dig into code to find who/when added all that to the master and what does it do.

google is your friend : https://www.sensorsmag.com/components/compensating-for-tilt-hard-iron-and-soft-iron-effects
Read and Learn.

Ps. It’s there since ages.

what are default values for those DIA params and how it could have been set to various values? i am dealing wiht some mishap in my configs, most likely.

Those parameters are set by compass calibration.