Manage Custom Attributes for Links by Using the Requirements Toolbox API

Establish Link Set

Load the crs_req requirement file, which describes a cruise control system. Find the link set named crs_req and assign it to a variable.

slreq.load('crs_req');
ls = slreq.find('Type','LinkSet','Name','crs_req')

ls = 
  LinkSet with properties:

             Description: 'crs_req'
                Filename: '/tmp/Bdoc24b_2725827_3713282/tpfec5b6fa/slrequirements-ex23809012/crs_req.slmx'
                Artifact: '/tmp/Bdoc24b_2725827_3713282/tpfec5b6fa/slrequirements-ex23809012/crs_req.slreqx'
                  Domain: 'linktype_rmi_slreq'
                Revision: 11
                   Dirty: 0
    CustomAttributeNames: {'Target Speed Change'}

Delete a Custom Attribute

There is an existing custom attribute in the link set called Target Speed Change. Delete the custom attribute and confirm the results by checking the existing custom attribute names for the link set.

deleteAttribute(ls,'Target Speed Change','Force',true);
ls.CustomAttributeNames

ans =

  0x0 empty cell array

Add a Custom Attribute of Each Type

Add a custom attribute of each type to the link set. Create an Edit custom attribute with a description.

addAttribute(ls,'MyEditAttribute','Edit','Description',['You can enter text as' ...
    ' the custom attribute value.'])

Create a Checkbox type attribute and set its DefaultValue property to true.

addAttribute(ls,'MyCheckboxAttribute','Checkbox','DefaultValue',true)

Create a Combobox custom attribute. Because the first option must be Unset, add the options 'Unset', 'A', 'B', and 'C'.

addAttribute(ls,'MyComboboxAttribute','Combobox','List',{'Unset','A','B','C'})

Create a DateTime custom attribute.

addAttribute(ls,'MyDateTimeAttribute','DateTime')

Check the custom attributes for the link set. Get information about MyComboboxAttribute to see the options you added to the Combobox attribute.

ls.CustomAttributeNames

ans = 1x4 cell
    {'MyCheckboxAttribute'}    {'MyComboboxAttribute'}    {'MyDateTimeAttribute'}    {'MyEditAttribute'}

atrb = inspectAttribute(ls,'MyComboboxAttribute')

atrb = struct with fields:
           name: 'MyComboboxAttribute'
           type: Combobox
    description: ''
           list: {'Unset'  'A'  'B'  'C'}

Set a Custom Attribute Value for a Link

Find a link in the link set and set the custom attribute value for all four custom attributes that you created.

lk = find(ls,'SID',3);
setAttribute(lk,'MyEditAttribute','Value for edit attribute.');
setAttribute(lk,'MyCheckboxAttribute',false);
setAttribute(lk,'MyComboboxAttribute','B');

Set MyDateTimeAttribute with the desired locale to ensure that the date and time is set in the correct format on systems in other locales. See Locale for more information.

localDateTimeStr = datestr(datetime('15-Jul-2018 11:00:00','Locale','en_US'),'Local');
setAttribute(lk,'MyDateTimeAttribute',localDateTimeStr);

View the attribute values.

getAttribute(lk,'MyEditAttribute')

ans = 
'Value for edit attribute.'

getAttribute(lk,'MyCheckboxAttribute')

ans = logical
   0

getAttribute(lk,'MyComboboxAttribute')

ans = 
'B'

getAttribute(lk,'MyDateTimeAttribute')

ans = datetime
   15-Jul-2018 11:00:00

Edit Custom Attributes

After you define a custom attribute for a link set, you can make limited changes to the custom attribute.

Add a description to MyCheckboxAttribute and MyComboboxAttribute, then change the list of options for MyComboboxAttribute. Because you cannot update the default value of Checkbox attributes, you can only update the description of MyCheckboxAttribute. View the changes.

updateAttribute(ls,'MyCheckboxAttribute','Description',['The checkbox value can be' ...
    ' true or false.']);
updateAttribute(ls,'MyComboboxAttribute','Description',['Choose an option from the ' ...
    'list.'],'List',{'Unset','1','2','3'});
atrb2 = inspectAttribute(ls,'MyCheckboxAttribute')

atrb2 = struct with fields:
           name: 'MyCheckboxAttribute'
           type: Checkbox
    description: 'The checkbox value can be true or false.'
        default: 1

atrb3 = inspectAttribute(ls,'MyComboboxAttribute')

atrb3 = struct with fields:
           name: 'MyComboboxAttribute'
           type: Combobox
    description: 'Choose an option from the list.'
           list: {'Unset'  '1'  '2'  '3'}

Find Links That Match Custom Attribute Value

Search the link set for all links where 'MyEditAttribute' is set to 'Value for edit attribute.'

lk2 = find(ls,'MyEditAttribute','Value for edit attribute.')

lk2 = 
  Link with properties:

           Type: 'Derive'
    Description: '#8: Set Switch Detection'
       Keywords: {}
      Rationale: ''
      CreatedOn: 20-May-2017 13:14:40
      CreatedBy: 'itoy'
     ModifiedOn: 05-Sep-2024 22:41:49
     ModifiedBy: 'batserve'
       Revision: 5
            SID: 3
       Comments: [0x0 struct]

Search the link set for all links where MyCheckboxAttribute is set to true.

lkArray = find(ls,'MyCheckboxAttribute',true)

lkArray=1×11 Link array with properties:
    Type
    Description
    Keywords
    Rationale
    CreatedOn
    CreatedBy
    ModifiedOn
    ModifiedBy
    Revision
    SID
    Comments

Search the link set for all links where MyComboboxAttribute is set to 'Unset'.

lkArray2 = find(ls,'MyComboboxAttribute','Unset')

lkArray2=1×12 Link array with properties:
    Type
    Description
    Keywords
    Rationale
    CreatedOn
    CreatedBy
    ModifiedOn
    ModifiedBy
    Revision
    SID
    Comments

Delete Custom Attributes

You can use deleteAttribute to delete attributes. However, because the custom attributes created in this example are assigned to links, you must set Force to true to delete the attributes. Delete MyEditAttribute and confirm the change.

deleteAttribute(ls,'MyEditAttribute','Force',true);
ls.CustomAttributeNames

ans = 1x3 cell
    {'MyCheckboxAttribute'}    {'MyComboboxAttribute'}    {'MyDateTimeAttribute'}

Add a new custom attribute, but don't set any custom attribute values for links.

addAttribute(ls,'NewEditAttribute','Edit');
ls.CustomAttributeNames

ans = 1x4 cell
    {'MyCheckboxAttribute'}    {'MyComboboxAttribute'}    {'MyDateTimeAttribute'}    {'NewEditAttribute'}

Because NewEditAttribute is not used by any links, you can delete it with deleteAttribute by setting Force to false. Confirm the change.

deleteAttribute(ls,'NewEditAttribute','Force',false);
ls.CustomAttributeNames

ans = 1x3 cell
    {'MyCheckboxAttribute'}    {'MyComboboxAttribute'}    {'MyDateTimeAttribute'}