Data tables store observation data, or measurements of various variables on a specific set of subjects. However, JMP data tables can also store metadata, or data about the data.
• Formulas
Table variables are for storing a single text string value, such as “Notes”. To understand how variables work, first get its existing value by sending a Get Table Variable message:
dt = Open( "$SAMPLE_DATA/Solubility.jmp" );
dt << Get Table Variable( "Notes" );
"Chemical compounds were measured for solubility in different solvents. This table shows the log of the partition coefficient (logP) of 72 organic solutes in 6 aqueous/nonpolar systems."
Now change the existing value of the string using Set Table Variable and then use Get Table Variable again to check that the string has been updated:
dt << Set Table Variable( "Notes", "Solubility of chemical compounds" );
dt << Get Table Variable( "Notes" );
"Solubility of chemical compounds"
The following example adds two new table variables to a data table:
dt = Open( "$DOCUMENTS/Big Class.jmp" );
myvar = "This is my version of the JMP Big Class sample data.";
dt << Set Table Variable( "key1", myvar );
dt << Set Table Variable( "key2", myvar );
Notice that setting the value creates a new variable only if one by the given name does not already exist. If you add two table variables with the same name, only one variable is created.