eval(attr(x = mod2$terms, which = "predvars")[[3]], envir = head(iris))
##              1           2
## [1,] 0.0635001 -0.04223695
## [2,] 0.0635001 -0.04223695
## [3,] 0.0635001 -0.04223695
## [4,] 0.0635001 -0.04223695
## [5,] 0.0635001 -0.04223695
## [6,] 0.1877627 -0.12257097
## attr(,"degree")
## [1] 3
## attr(,"knots")
## 50% 
## 1.3 
## attr(,"Boundary.knots")
## [1] 0.1 2.5
## attr(,"intercept")
## [1] FALSE
## attr(,"class")
## [1] "ns"     "basis"  "matrix"