I want to get rid of the sign in front of the element, but the symbol variables are involved, so I can't use the Abs
function to get rid of the sign.
I want this list {-1, -2, +3, 4, -x, +x, -Fx[3], +Fx[3]}
to be processed to {1, 2, 3, 4, x, x, Fx[3], Fx[3]}
.
In addition, What should I do when the list contains a ± sign? For example, when the list is {-1, -2, +3, 4, -x, +x, -Fx[3], +Fx[3], -Fx[-3], ±Fy[-2] ,±Fy[±x]}
.