partial match of 2 string vectors with different lenghts

Hi everyone,

I hope you can help me. I have two 2 string arrays (str1 and str2) with different lengths. For instance,

str1= ["16-10-2017 09:20:00"; "16-10-2017 09:21:00"; "16-10-2017 09:22:00"; "16-10-2017 09:23:00"] ]

str2= ["16-10-2017 09:21:00_water"; "16-10-2017 09:23:00_coffee"] ]

I would like to:

(1) match the first 19 characters of a str2 (in this case it is 16-10-2017 09:21:00) with str1

(2) create str3 that will give me a string array like this str3=[0;"16-10-2017 09:21:00_water";0;"16-10-2017 09:23:00_coffee"] So when there is an overlap use the value in str2 in str3, when there is no overlap use 0 or NAN.

Thanks,

Answer 1

[Rik]

Something like this:

str1= ["16-10-2017 09:20:00"; "16-10-2017 09:21:00"; "16-10-2017 09:22:00"; "16-10-2017 09:23:00"];
str2= ["16-10-2017 09:21:00_water"; "16-10-2017 09:23:00_coffee"];
temp=arrayfun(@extract_date,str2);
L=ismember(str1,temp);
str3=str1;
str3(~L)=0;
str3(L)=str2;

function date=extract_date(str)
str=char(str);
date=string(str(1:19));
end

[Paolo]

I tested this for:

 str1= ["16-10-2017 09:20:00"; "16-10-2017 09:21:00"; "16-10-2017 
 09:22:00"; "16-10-2017 09:23:00"];
 str2= ["16-10-2017 09:21:00_water"];

And got str3 =

4×1 string array

    "16-10-2017 09:21:00_water"
    "0"
    "16-10-2017 09:21:00_water"
    "16-10-2017 09:21:00_water"

From my understanding the correct output should be:

 str3=[0;"16-10-2017 09:21:00_water";0;0]

[Rik]

Sorry, my mistake, I switched up the ~L and L. I'll edit my answer.

[Paolo]

+1, nice solution!

[PH]

Thanks, the code works with these strings. However, I tried the code with my original data and it did give me an error. str1's value is 6196x1 and str2's value is 14x1.

(In an assignment A(:) = B, the number of elements in A and B must be the same. Error in matching_code (line 5) str3(L)=str2;)

[Rik]

Then the dates in str2 are non-unique. So which should be selected?