Equations tags

Flagging equations with tags

Usecases

Find the equation corresponding to nonzero residuals

resid_with_names.m

Details about the implementation

• Add general labels to equations. In the current prototype a list of key-values pair can be written in brackets before each equation :

[key='value',key='value',...] y = y + 1;

One may want to attach values of any type to an equation. Currently, only strings of characters are recognized but we ask the user to specify users to enter quoted strings nevertheless. Type of keys should also be restricted so that they can be used as fields in matlab structures if needed, i.e. no numeric character, no space,...

• Structure in the preprocessor is the same as in Matlab and mimics a database table : an array with 3 columns. It is stored in M_.equations_tags as in :

M_.equations_tags = {
    1 'name' 'First equation';
    2 'name' 'Second equation';
    2 'portfolio' 'true';
};

• It is easy to query this table in matlab as follows

tags = M_.equations_tags;
tags(cell2mat(tags(:,1))==2,2:3) % all tags for equation 2
tags(strmatch('name',tags(:,2)),[1 3]) % a vector with equations numbers and associated names