It's even in the documentation to Units: > But Fahrenheit to Celsius is linear, you insist. Not so. A transformation T is linear if T(x+y)=T(x)+T(y) and this f

It's even in the documentation to Units: > But Fahrenheit to Celsius is linear, you insist. Not so. A transformation T is linear if T(x+y)=T(x)+T(y) and this fails for T(x)=ax+b . This transformation is affine, but not linear. https://www.gnu.org/software/units/manual/html_node/Overview.html#Overview https://www.gnu.org/software/units/manual/html_node/Overview...