Auto-generate self-sensitivities for placeholder expressions
Currently, on a PlaceHolder
Expression, we hang zero expression calculations when the placeholder corresponds to an independent variable and we want sensitivity w.r.t. a different independent variable.
However, we are not creating expressions for dy/dy=1
on placeholders. This is problematic because it requires awkward workarounds for those sensitivity values.
Auto-generate dy/dy=1
when y
is an independent variable and a placeholder.