HELP WITH ESTRACT SUBSTRING OF STRING

good, I wish to raise my problem, because I know how to do. I, for example have a long string as follows:

[3 -1 -1 -1 -1 -1 1 -1 -1 -1 0 -1 -1 -1 -1 4 -1 0 -1 -1 -1 0 -1 -1 3 -1 -1 -1 -1 -1 -1 4 -1 -1 0

-1 1 -1 -1 -1 0 -1 1 -1 -1 -1 -1 -1 -1 1 -1 0 -1 -1 4……..

What I want to do is the following:

1) extracting substrings so that starts for next 3/4 and ends 3/4 including the upcoming latter. For example:

[-1 -1 -1 -1 -1 1 -1 -1 -1 0 -1 -1 -1 -1 4]

Next substring;

[-1 0 -1 -1 -1 0 -1 -1 3]

Next substring;

[-1 -1 -1 -1 -1 -1 4]

And so on

Answer 1

[Walter Roberson]

http://www.mathworks.com/help/matlab/matlab_prog/regular-expressions.html#brchk1t

regexp(String, '(?<=[34]).*?[34]', 'match')

Or so I figure as I drift off to sleep.

Answer 2

[Andrei Bobrov]

 a = [3 -1 -1 -1 -1 -1 1 -1 -1 -1 0 -1 -1 -1 -1 4 -1 0 -1 -1 -1 0 -1 -1 3 -1 -1 -1 -1 -1 -1 4 -1 -1 0  -1 1 -1 -1 -1 0 -1 1 -1 -1 -1 -1 -1 -1 1 -1 0 -1 -1 4];

 l = a == 3 | a== 4;
 l(2:end-1) = circshift(l(2:end-1),[0 1]);
 l(end) = 0;
 out = accumarray(cumsum(l(:)),a(:),[],@(x){x});

[FRANCISCO]

I wanted to ask something else I do not know how I can do it :

The end result should look like the following , for example :

a) [ -1 -1 -1 0 -1 1 -1 4 ] started with this sequence

MATRIX1 ( the length of the substring is n = 3)

PATTERN________________OCCURS________________________-Nº(-1)

0 1 4---------------------------------------1----------------------------------------------------5

eliminating pattern we get (-1 ) So if another pattern appears the same size as this matrix include , for example :

b) [-1 -1 1 -1 0 3]

PATTERN________________OCCURS________________________-Nº(-1)

0 1 4---------------------------------------1----------------------------------------------------5

1 0 3---------------------------------------1----------------------------------------------------3

So if another pattern appears, but of varying length I store in another array , for example :

c ) [ 1 -1 0 -1 -1 -1 1 -1 4]

MATRIX2 ( the length of the substring is n = 4)

PATTERN________________OCCURS________________________-Nº(-1)

1 0 1 4---------------------------------------1---------------------------------------------------5

My question is, how can I remove the numbers with a loop (-1) for the pattern, and I store it in another array each pattern of the same length?

Before deleting (-1) should make a count and associate to pattern.

Many thanks

[FRANCISCO]

To count (-1) I used:

if true

    % code

n=length(out);

for i=1:n;

    gg=out(i,1);

    gg=cell2mat(gg);

    menos1(i)=numel(gg(gg==-1));

end

menos1=menos1';

end

And to remove (-1) I tried to use this code but matlab gives me error

if true

    % code

out1=out;

n=length(out1);

for i=1:n;

    gg=out1(i,1);

    gg=cell2mat(gg);

    gg(gg(i)==-1)=[];

end

end

Many thanks

Answer 3

[Jos (10584)]

If you have version 2013b, there is a function called strsplit , that might work on numerical arrays (like strfind used to do). I cannot test this, though.

C = strsplit(str,[3 4])