How read string or enumeration from excel and convert to numeric values in matlab script

ex:

READ

GREEN

YELLOW

read from excel sheet and convert into numeric values (READ =1, GREEN =2, YELLOW=3)

[Steven Lord]

What are you hoping to do with these numeric values afterwards?

Do you specifically want READ (I assume a typo and it's actually supposed to be RED) to be 1 and GREEN to be 2 etc., or is that just because that's the order they happened to appear in the file?

You may want to read the data in as a categorical array. If you don't actually need them to be numbers but just need them to be usable as grouping variables in calculations like groupsummary, grouptransform, etc. then that would be easiest.

[VINAY]

What are you hoping to do with these numeric values afterwards?

need to feed into the simulink blocks (for better understading)

Answer 1

[Deepak]

Hi @VINAY,

I understand that you want to read string values like 'RED', 'GREEN', 'YELLOW' from an Excel sheet and convert them into numeric codes (e.g., RED = 1, GREEN = 2, etc.) to feed into Simulink blocks. You can do this by reading the data using "readtable", then mapping the strings to numbers using either a "containers.Map", "dictionary" (for R2022b and later), or a "categorical" array. For example, dictionary(["RED","GREEN","YELLOW"], [1,2,3]) allows you to convert a string array to numeric values with a simple lookup.

Once you have the numeric values, you can pass them into Simulink using a Constant block for static input, or a From Workspace block if you want to feed a time-based signal (e.g., for simulation). This is a common approach for mapping enums or string labels into Simulink-compatible numeric formats.

Please find attached the relevant documentation for reference:

Read Spreadsheet data into table: www.mathworks.com/help/matlab/import_export/read-spreadsheet-data-into-table.html

containers.Map: www.mathworks.com/help/matlab/ref/containers.map.html

I hope this helps.