Import data from txt file

Hi there,

my txt file looks like this: (see attached txt file)

What I try to get is a simple table with lines like this:

frame; timestamp [s]; loc_x; loc_y; loc_z

1007; 52045.728; -135.966; 225.786; -52.285

1008; 52045.745; -135.966; 225.786; -52.285

How can I do this? Thanks

[Adam Danz]

I see the frame and timestamp components. Where are the xloc yloc etc.?

What are the numbers 1007; 52045.728; -135.966; 225.786; -52.285?

frame 1010 ts 52045.778 nbod 4 nfly 0 nmea 0 nmearef 0 nhand 0 nmar 0 nhuman 0 ninertial 4
bod 0 not tracked
bod 1 not tracked
bod 2 qu 1.000 loc -135.967 225.786 -52.283 rot -0.282 -0.960 0.001 0.960 -0.282 -0.008 0.008 -0.001 1.000
bod 3 not tracked
no human model data
 inertial body 0 st 0 error 0.000
 inertial body 1 st 0 error 0.000
 inertial body 2 st 2 error 0.000
 loc -135.967 225.786 -52.283 rot -0.282 -0.960 0.001 0.960 -0.282 -0.008 0.008 -0.001 1.000
 inertial body 3 st 0 error 0.000

[Rik]

Do you need code that only works on this file, or should it also handle multiple bodies being tracked?

What have you tried so far on your own?

[Ferdinand Grosse-Dunker]

In line 1 of each block is the frame number (1007) and the timestamp (52045.728 seconds)

In line 10 of each block is the location and rotation data. Starting with location (loc_x, loc_y, loc_z) then rotation (rot_xx, rot_xy, rot_xz; rot_yx, rot_yy, rot_yz; rot_zx, rot_zy, rot_zz).

All other lines of each block are not necessary.

Answer 1

[Adam Danz]

This uses readtable() to read in your txt file and it uses regexp() with the 'tokens' flag to pull out relevant data.

%% Import data into table
opts = delimitedTextImportOptions("NumVariables", 1);
opts.DataLines = [1, Inf];
opts.VariableNames = "txt";
test1 = readtable("test1.txt", opts);  %file is on path

%% Extract desired data 
% Pull out the frame and ts data
tokens = regexp(test1.txt, 'frame (\d+) ts (\d+.\d+)', 'tokens');
frame_ts = cell2mat(cellfun(@str2double,[tokens{:}]','UniformOutput',false));

% Pull out loc coordinates 
tokens = regexp(test1.txt, '^loc (-?\d+.\d+) (-?\d+.\d+) (-?\d+.\d+)', 'tokens'); 
loc = cell2mat(cellfun(@str2double,[tokens{:}]','UniformOutput',false));

% Check that frame_ts and loc have same number of rows.
if size(frame_ts,1) ~= size(loc,1)
    error('''frame_ts'' and ''loc'' have different number of rows.')
end

%% Put data into table
T = array2table([frame_ts, loc], 'VariableNames', {'frame', 'timestamp', 'loc_x', 'loc_y', 'loc_z'});

% inspect first few rows
head(T)

Result

format long

>> head(T)
ans =
  8×5 table
    frame    timestamp     loc_x       loc_y      loc_z 
    _____    _________    ________    _______    _______
    1007     52045.728    -135.966    225.786    -52.285
    1008     52045.745    -135.966    225.786    -52.285
    1009     52045.761    -135.967    225.786    -52.283
    1010     52045.778    -135.967    225.786    -52.283
    1011     52045.795    -135.967    225.786    -52.283
    1012     52045.811    -135.967    225.786    -52.283
    1013     52045.828    -135.967    225.786    -52.283
    1014     52045.845    -135.967    225.786    -52.283

Answer 2

[Ferdinand Grosse-Dunker]

This works great! Thanks a lot Adam!

[Adam Danz]

Glad I could help!