Import text file signal data in Matlab-CodePudding

Have tried to understand how to import text file data (time signal) in Matlab, can you please help. Structure of .txt file looks like this:

0,0006 0,0835 0,0013 0,0016 0,0019 0,0082 0,0026 -0,0193 0,0032 0,1115 0,0039 -0,1169 0,0045 0,0461 0,0052 -0,1185 0,0058 0,0048 0,0065 0,0087 0,0071 -0,1163 0,0078 0,0913 0,0084 0,022 0,0091 0,0072 0,0097 -0,0829

in original file it looks like to column separated by tab space:

CodePudding user response：

Just replace commas by dots and use dlmread function:

cat signal.txt
0.0006 0.0835
0.0013 0.0016
0.0019 0.0082
0.0026 -0.0193
0.0032 0.1115
0.0039 -0.1169
0.0045 0.0461
0.0052 -0.1185
0.0058 0.0048
0.0065 0.0087
0.0071 -0.1163 
0.0078 0.0913 
0.0084 0.022
0.0091 0.0072
0.0097 -0.0829

format long
data=dlmread('signal.txt',' ',0,0)
data =

   5.999999999999999e-04   8.350000000000000e-02
   1.300000000000000e-03   1.600000000000000e-03
   1.900000000000000e-03   8.200000000000001e-03
   2.600000000000000e-03  -1.930000000000000e-02
   3.200000000000000e-03   1.115000000000000e-01
   3.900000000000000e-03  -1.169000000000000e-01
   4.500000000000000e-03   4.610000000000000e-02
   5.200000000000000e-03  -1.185000000000000e-01
   5.800000000000000e-03   4.800000000000000e-03
   6.500000000000000e-03   8.699999999999999e-03
   7.100000000000000e-03  -1.163000000000000e-01
   7.800000000000000e-03   9.130000000000001e-02
   8.399999999999999e-03   2.200000000000000e-02
   9.100000000000000e-03   7.200000000000000e-03
   9.700000000000000e-03  -8.290000000000000e-02

Disclaimer: I don't have MATLAB on my computer and therefore used Octave. Based on my previous experience, it should work in MATLAB as well.

CodePudding user response：

This can be done using three steps:

file_string = fileread('my_file.txt');       % Read file contents to string.

file_string = strrep(file_string, ',', '.'); % Replace commas in string to periods.

file_mat = str2num(file_string);             % Convert contents to a matrix.

The original questions states that the columns are separated by tab and it appears that the rows are separated by a line feed in the figure, but in the text, rows are also separated by tabs. If the file uses line feeds to separate rows, then the result file_mat will already be formatted into rows and columns. If tabs are used to separate all elements (columns and rows), then file_mat will contain a vector only. If this is the case, then file_mat can be reshaped using the following:

file_mat = reshape(file_mat, [2 length(file_mat)/2])'; % Convert vector to array with two columns.