Nested Indexing in a Single Line command
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Is it possible to extract different data in the following structured string using a single line command?
exp={'George: A5 == BB';...
'Anna: C3 == DD';...
'Smith: E2 == FFF';...
'Ken: G8 == HHHH'};
For example, the obvious method to extract HHHH is the following:
mystr1=split(exp(end),': ',2);
mystr2=split(mystr1(:,2),' == ',2);
mystr2(end)
Can you suggest a single line of command to extract HHHH? Please note all names, right-hand and left-hand sides of the equations can be anything with different lenghts or characters. Only : and == characters are unchanged. The code needs be be universal meaning it sould extract anything (index 3 and 1 for Smith or index 2 and 2 for C3 or index end and end for HHHH) only using a single line command.
4 Comments
Bob Thompson
on 14 Jan 2019
So, all you're looking to do is display the answer? This can be done by unsurpressing the regexp command (remove the semicolon at the end of the line).
Accepted Answer
Steven Lord
on 14 Jan 2019
Using the answer from Bob Nbob's comment:
mystr = regexp(exp{end},'\W','split'); mystr = mystr{end};
That's one line (albeit not one command.)
The type of indexing you asked about doesn't exist, at least not directly. You could write an explicit call to subsref to get that in one command, but in my opinion it would be much less clear than writing those two commands.Is there a particular reason why you need it in one command?
If you want to do this to use this in an anonymous function inside a script, and you're using release R2016b or later instead consider creating a local function inside your script file.
More Answers (1)
Stephen23
on 14 Jan 2019
Edited: Stephen23
on 14 Jan 2019
>> C = {'George: A5 == BB'; 'Anna: C3 == DD'; 'Smith: E2 == FFF'; 'Ken: G8 == HHHH'};
>> D = regexp(C,'^(\w+):\s*(\w+)\s*==\s*(\w+)','tokens','once');
>> horzcat(D{:}) % or VERTCAT, depending on your needs.
ans =
[1,1] = George
[2,1] = A5
[3,1] = BB
[1,2] = Anna
[2,2] = C3
[3,2] = DD
[1,3] = Smith
[2,3] = E2
[3,3] = FFF
[1,4] = Ken
[2,4] = G8
[3,4] = HHHH
4 Comments
Walter Roberson
on 14 Jan 2019
C = {'George: A5 == BB'; 'Anna: C3 == DD'; 'Smith: E2 == FFF'; 'Ken: G8 == HHHH'};
disp(char(regexprep(C, '^.*==\s*', '')))
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