How to write a regular expression to extract a vector ([6.300000​000000001,​0.1,-7.5]) using regexp?

I have data that reads in as a 1 x 102740 char. I am trying to extract the vectors using regexp and format it as a n x 3 table.

Here is some of the data for example:

data='[{"name":"accX","units":"m/s2"},{"name":"accY","units":"m/s2"},{"name":"accZ","units":"m/s2"}],"values":[[7.4,0.2,-6.4],[6.300000000000001,0.1,-7.5],[8.1,0.8,-0.5],[9.700000000000001,2.7,0],[11.100000000000001,1.9000000000000001,-1.2000000000000002]';4

I am trying to use regexp but cannot format the expression correctly.

How can I format the expression to basically get only the vectors?

expression='^[\d*,\d*,\d*]$'; %this is what I have tried but it returns a 0x0 cell
x=regexp(data,expression,'match');

For example, from the data above, I need to only extract:

[[7.4,0.2,-6.4]

[6.300000000000001,0.1,-7.5]

[8.1,0.8,-0.5]

[9.700000000000001,2.7,0]

Ideally I would like to format the vectors into a n by 3 table with columns for x, y, and z.

So it would look something like:

x=[7.4; 6.300000000000001; 8.1; ...]

y=[0.2; 0.1; 0.8; ...]

z=-[6.4; ,-7.5; -0.5; ...]

Thank you in advance

[Akira Agata]

Is it a JSON data?

If so, jsondecode function would be help.

[Tiffany Sorto]

@Akira Agata Thank you so much! I didn't know about this function.

Answer 1

[DGM]

Akira's comment may be very relevant, but since I'm unfamiliar with handling JSON, I'll just throw down a regex kludge as requested:

data = '[{"name":"accX","units":"m/s2"},{"name":"accY","units":"m/s2"},{"name":"accZ","units":"m/s2"}],"values":[[7.4,0.2,-6.4],[6.300000000000001,0.1,-7.5],[8.1,0.8,-0.5],[9.700000000000001,2.7,0],[11.100000000000001,1.9000000000000001,-1.2000000000000002]';

numexpr = '[+-]?(\d*\.)?\d+';
expr = [numexpr ',' numexpr ',' numexpr];
A = regexp(data,expr,'match').';
A = str2double(split(A,','))

A = 5×3

7.4000 0.2000 -6.4000 6.3000 0.1000 -7.5000 8.1000 0.8000 -0.5000 9.7000 2.7000 0 11.1000 1.9000 -1.2000

I'm sure this could be simplified or made more robust, but eh.

[Tiffany Sorto]

@DGM Thank you! This worked as well. I have not used the regexp function before and creating the regular expression was very confusing

[DGM]

Yeeeah. Regex can be confusing. :D