Moving from Julia 0.6 to 1.1

By: Sören Dobberschütz

Re-posted from: http://sdobber.github.io/movingtojulia11/

Finally, all files in the GitHub repository have been updated to be able to run on Julia 1.1. In order to be able to run them (at the time of writing), the developmental versions of the Tensorflow.jl and PyCall.jl packages need to be installed. Some notable changes are listed below:

General

  • The shuffle command has been moved to the Random package as Random.shuffle().
  • linspace has been replaced with range(start, stop=..., length=...).
  • To determine the length of a matrix, use size(...,2) instead of length().
  • For accessing the first and last part of datasets, head() as been replaced with first(), and tail() with last().
  • For arithmetic calculations involving constants and arrays, the better syntax const .- array needs to be used instead of const - array. In connection with this, a space might be required before the operator; i.e. to avoid confusion with number types use 1 .- array, and not 1.-array.
  • Conversion of a dataframe df to a matrix can be done via convert(Matrix, df) instead of convert(Array, df).

Exercise 8

  • The creation of an initially undefined vector etc. now requires the undef keyword as in activation_functions = Vector{Function}(undef, size(hidden_units,1)).
  • An assignment of a function to multiple entries of a vector requires the dot-operator: activation_functions[1:end-1] .= z->nn.dropout(nn.relu(z), keep_probability)

Exercise 10

  • For this exercise to work, the MNIST.jl package needs an update. A quick fix can be found in the repository together with the exercise notebooks.
  • Instead of flipdim(A, d), use reverse(A, dims=d).
  • indmax has been replaced by argmax.
  • Parsing expressions has been moved to the Meta package and can be done by Meta.parse(...).

Exercise 11

  • The behaviour of taking the transpose of a vector has been changed – it now creates an abstract linear algebra object. We use collect() on the transpose for functions that cannot handle the new type.
  • To test if a string contains a certain word, contains() has been replaced by occursin().