What does ix=ismembe​r(vars,["s​tate","sou​rce"])| contains(vars,["lat", "lon", "timestamp", "damage", "event"]); do?

What does the code line

ix=ismember(vars,["state","source"])| contains(vars,["lat", "lon", "timestamp", "damage", "event"]);

in the Matlab Example https://ch.mathworks.com/de/videos/importing-your-data-into-matlab-1567682718882.html actually do?

As far as I understand, the ix of each row is 1 when "state" and "source" or ["lat", "lon", "timestamp", "damage", "event"] are in the vars-string. Is this correct?

[Stephen23]

Where any element of vars is either:

• equal to "state"
• equal to "source"
• contains "lat"
• contains "lon"
• contains "timestamp"
• etc.

the corresponding element of the output IX will be TRUE, otherwise the element will be FALSE.

Answer 1

[KSSV]

idx1=ismember(vars,["state","source"]) ;   % gives logical indexing where state, source are presnt in vars 
idx2 = contains(vars,["lat", "lon", "timestamp", "damage", "event"]); % gives logical indices where loat, lon etc are present in vats
ix = idx1 | idx2 ;   % gives logical indexing of or of the above indices 

[Stephen23]

"presnt in" is ambiguous: does that mean that they must be an exact match, or just match substrings?

[KSSV]

Must be a exact match.

[Marcel345614]

Thanks a lot for these answers! But one question: Why are there two functions, which do the same thing?

I mean

ix=ismember(vars,["state","source"])| ismember(vars,["lat", "lon", "timestamp", "damage", "event"]); 

would be aquivalent, or where is my mistake?

Second question: According to help vars should be in ["stats", "source"]? Shouldn't this be the opposite?:

ismember(["state","source"],vars)

help: Lia = ismember(A,B) returns an array containing logical 1 (true) where the data in A is found in B. Elsewhere, the array contains logical 0 (false).

[KSSV]

contains is used for strings...... you can check the output of each and comapre yourself to find out are they same or not.

[Stephen23]

"Why are there two functions, which do the same thing?"

They don't do the same thing.

[Marcel345614]

Thanks!

What about my second question? (Sorry, it seems that I have edited to late)