readyaml

MATLAB function to read yaml files. Outputs result into struct.

Installation

clone this repository by typing in your command window:

git clone https://github.com/MaartenJongeneel/readyaml.git

Then, in MATLAB, you can add this folder and functions to your path via

addpath(genpath('path/to/readyaml'));

Usage

You can simple read out your yaml file in matlab via

yamlFile = 'path/to/my/file.yaml';
YamlStruct = readyaml(yamlFile);

Limitations

As keys will be written to MATLAB struct names, they name of the key should be compatible with what MATLAB can have as struct names. This means a key must begin with a letter, can contain letters, digits, or underscore characters, and are case sensitive and keys cannot contain periods.

test:
  1note: this is an invalid fieldname in MATLAB
  note1: this is a valid fieldname in MATLAB
  note.1: this is also invalid in MATLAB

As MATLAB cannot have a struct with duplicate fieldnames, it will automatically overwrite existing keys of the YAML file. As a result, in the example below, only the second note will be saved, as it will overwrite the first note.

test:
  note: this is a comment
  note: but this comment will overwrite the previous one, due to duplicate key names

Testing

We have provide a test.yml file, that that can be used to test out the function. It contains some comments, objects, lists, numerical arrays, and matrices to show what can be stored.

Posibilities

Current form of the yaml parcer supports the following:

• Ordinary comments

  #ordinary comments can start anywhere on a line

• Key value pairs

  key: value

• Lower levels key value pairs

  person:
    name: John
    age: 34

• Ordinary lists

  person:
    - John
    - Rae

• Lists with nested objects

  persons:
    - name: John
      age: 34
    - name: Rae
      age: 4

• Sequences of keys like

  person:
    - [name, age]: [Rae Smith, 4] 
    - [name, age]: [John, 34] 

• Matrices (list of numerical arrays)

  matrix:
    - [0, 1, 2]
    - [3, 4, 5]
    - [6, 7, 8]

• List with objects that contain list of objects etc.

  example:
    - martin:
        name: Martin D'vloper
        job: Developer
        skills:
          - python: good
          - perl: good
          - pascal: moderate
    - tabitha:
        name: Tabitha Bitumen
        job: Developer
        skills:
          - lisp: good
          - fortran: moderate
          - erlang: novice

• Possibility of inline blocks like

  example:
    - {name: John Smith, age: 33}
    - {name: John Doe, age: 41}

To Do

In current form, the following components are still missing:

• Multi-line strings using | and > characters

  data: |
    There once was > [] a tall man from Ealing
    Who got on a bus to Darjeeling
        It said on the door
        "Please don't sit on the floor"
    So he carefully sat on the ceiling
  data: >
    Wrapped text
    will be folded
    into a single
    paragraph
  
    Blank lines denote
    paragraph breaks

• Node anchors (using &) and references (using *)

  - step:  &id001                  # defines anchor label &id001
      instrument:      Lasik 2000
      pulseEnergy:     5.4
      pulseDuration:   12
      repetition:      1000
      spotSize:        1mm
  
  - step: &id002
      instrument:      Lasik 2000
      pulseEnergy:     5.0
      pulseDuration:   10
      repetition:      500
      spotSize:        2mm
  - Instrument1: *id001   # refers to the first step (with anchor &id001)
  - Instrument2: *id002   # refers to the second step

Author

Maarten J. Jongeneel, Ph.D. researcher
Eindhoven University of Technology (TU/e), Mechanical Engineering Dept.
Contact: email