fn prev_el(&self, i: usize) -> Option<&Element> {
        let el = &self.elements[self.prev_ix(i)];
        if (i > 1 || self.is_closed) && el.is_smooth() {
            Some(el)
        } else {
            None
        }
    }
/// The previous element that has a G2 continuity constraint.
The previous element that has a G2 continuity constraint.
The previous element that has a G2 continuity constraint .
fn prev_el(&self, i: usize) -> Option<&Element> {
        let el = &self.elements[self.prev_ix(i)];
        if (i > 1 || self.is_closed) && el.is_smooth() {
            Some(el)
        } else {
            None
        }
    }
fn prev_el ( & self , i : usize ) -> Option < & Element > { let el = & self . elements [ self . prev_ix ( i ) ] ; if ( i > 1 || self . is_closed ) && el . is_smooth ( ) { Some ( el ) } else { None } }
The previous element that has a G2 continuity constraint.
The previous element that has a G2 continuity constraint .
&self
i
usize
&self
i
usize