func(deriv,{
  (([x]([y]+[z]))
  -([x]([y]-[z]))) / (2*[z])
}):

func(linapx,{
  [y] - ([x]([y]))/deriv([x],[y],[z])
}):

func(secderiv, {
  (([x]([y]+[z])) + ([x]([y]-[z]))
  - 2*([x]([y]))) / ([z]*[z])
}):

func(newton,{
  iff(
    (greater(0.000001,abs([x]([y]))))
    |(greater(abs([x]([y])),1000000)),
    {[y]},
    {newton([x],
      linapx([x],[y],0.001))})}):

func(rsum,{sub({
  let(dx,([z]-[y])/[t]):
  let(ls,0):let(rs,0):let(ms,0):
  let(ts,0):let(si,0):let(j,0):
  [t]:do:
    let(xj,[y] + [j]*[dx]):
    let(x1,[xj] + [dx]):
    let(xm,([xj] + [x1])/2):
    let(ls,[ls] + [dx]*([x]([xj]))):
    let(rs,[rs] + [dx]*([x]([x1]))):
    let(ms,[ms] + [dx]*([x]([xm]))):
    let(j,[j]+1):loop:
  let(ts,(1/2)*([ls]+[rs])):
  let(si,(1/3)*([ts]+2*[ms])):
  print_[si]})}):

print_`calculus.txt',: