String with mask parameter

On my project, I am using a sub-system with a mask which takes a string as a parameter (typically called "topic_name").

Up to now that topic_name is always populated manually (i.e. typing the string whenever we create a new IO).

However, this is time consuming to maintain a system with multiple occurences where just a number changes in the string.

e.g. for the iteration of my "item1", I map various sub-systems with strings "item1/pump1", "item1/pump2", "item1/cold_valve", "item1/hot_valve"... Then I need to do the same with "item2", mapping strings "item2/pump1", "item2"/pump2", "item2/cold_valve", "item2/hot_valve". And so on with item3, item4, etc.

In short this is a nightmare to maintain, and since all items have the same structure, I would like to create a library block using a mask parameter "item_number" so that I can create the mapping once for pump1, pump2, cold_valve, hot_valve, then just populate the item_number for all the instances of item.

Can anyone explain what the syntax would be for itemitem_number/pump1?

Answer 1

[Matt J]

For example,

"item" + (0:3)' + "/" + ["pump1" "pump2" "cold_valve" "hot_valve"]

ans = 4×4 string array
    "item0/pump1"    "item0/pump2"    "item0/cold_valve"    "item0/hot_valve"
    "item1/pump1"    "item1/pump2"    "item1/cold_valve"    "item1/hot_valve"
    "item2/pump1"    "item2/pump2"    "item2/cold_valve"    "item2/hot_valve"
    "item3/pump1"    "item3/pump2"    "item3/cold_valve"    "item3/hot_valve"

[julien dannenmayer]

Thanks Matt,

However, due to other constraints, I would need " (0:3)' " to be a function argument or a parameter, so that I can write something like

"item" + item_ number + "pump1"

When I try that, I get error "Convertion to uint8 from string is not possible". And if I for item_number to be a string input, I get error "Arrays have incompatible sizes for this operation".

It's like all the basics of string manipulation (including https://nl.mathworks.com/help/matlab/matlab_prog/converting-from-numeric-to-string.html) are discarded...

[julien dannenmayer]

For info, I figured that the external library block that I was using required this string to be a char type.

After typecasting, I could get it to work