/// If this feature is a placeholder for 'the k-th color is null', returns Some(k)
/// else returns None.
If this feature is a placeholder for 'the k-th color is null', returns Some(k)
else returns None.
If this feature is a placeholder for ' the k - th color is null ' returns Some ( k ) else returns None .
fn null(&self, i: usize) -> Option<u32> {
        let num_nonnull_features = self.nfeatures.try_into().unwrap();
        if self.cfc[i].feature_idx >= num_nonnull_features {
            Some(self.cfc[i].feature_idx - num_nonnull_features)
        } else {
            None
        }
    }
fn null ( & self , i : usize ) -> Option < u32 > { let num_nonnull_features = self . nfeatures . try_into ( ) . unwrap ( ) ; if self . cfc [ i ] . feature_idx >= num_nonnull_features { Some ( self . cfc [ i ] . feature_idx - num_nonnull_features ) } else { None } }
If this feature is a placeholder for 'the k-th color is null', returns Some(k)
else returns None.
If this feature is a placeholder for ' the k - th color is null ' returns Some ( k ) else returns None .
&self
i
usize