Owl's Tutorial at CUFP 2017

readme.md

Owl's Tutorial at CUFP 2017

This zoo gist contains the material including dataset, code, and presentation slides for Owl's tutorial at CUFP in Oxford.

Please contact Liang Wang ryanrhymes@gmail.com if you have any questions.

Liang @ Cambridge, UK, 2017

gist.id

c18fdd78b99283a102a721a0fe4f214b

tutorial.ml

#!/usr/bin/env owl

open Owl

let t1_load_data () =
  let x = Mat.uniform 500 1 in
  let p = Mat.uniform 1 1 in
  let y = Mat.(x *@ p + gaussian ~sigma:0.05 500 1) in
  x, y


let t1_sol () =
  let x, y = t1_load_data () in
  let h = Plot.create "plot_t1.png" in
  let a, b = Linalg.D.linreg x y in
  let y' = Mat.(x *$ b +$ a) in
  Plot.scatter ~h x y;
  Plot.plot ~h ~spec:[ RGB (0,255,0) ] x y';
  Plot.output h


let t2_sol () =
  let open Algodiff.D in
  let x = Owl.Mat.linspace 0. 3. 100 in
  let f x = Maths.(sin x) in
  let y2 = (f |> diff |> diff) (Mat x)  |> unpack_mat in
  let y3 = (f |> diff |> diff |> diff) (Mat x)  |> unpack_mat in

  let open Algodiff.Numerical in
  let g x = Pervasives.(sin x) in
  let z2 = Owl.Mat.map (g |> diff |> diff) x in
  let z3 = Owl.Mat.map (g |> diff |> diff |> diff) x in

  let h = Plot.create "plot_t2.png" in
  Plot.(plot ~h ~spec:[ LineStyle 2; RGB (255,0,0) ] x y2);
  Plot.(plot ~h ~spec:[ LineStyle 1; RGB (255,0,0) ] x y3);
  Plot.(plot ~h ~spec:[ LineStyle 2; RGB (0,255,0) ] x z2);
  Plot.(plot ~h ~spec:[ LineStyle 1; RGB (0,255,0) ] x z3);
  Plot.output h


let _ = print_endline "Welcome to Owl's Tutorial"