reading decimal number with GUI matlab - matlab

I am developing a user interface using matlab wich allows to browse and load a text file and display some curves. I am facing a problem, my file text is a set of decimal number, matlab is reading those number as two columns.
this is an exemple: u find here the file that I am working on:
After runing this code :
[filename pathname] = uigetfile({'*.txt'},'File Selector');
fullpathname = strcat(pathname,filename);
text = fileread(fullpathname); %reading information inside a file
set(handles.text6,'string',fullpathname)%showing full path name
set(handles.text7,'string',text)%showing information
loaddata = fullfile(pathname,filename);
xy = load(loaddata,'-ascii','%s');
t = xy(:,1);
i = xy(:,3);
handles.input1 = i;
handles.input2 = t;
axes(handles.axes1);
plot(handles.input1,handles.input2)
the curves looks so strenge, so I checked the result of xy= load(loaddata,'-ascii') using command window and here the problem appears!
So I have now 12 columns instead of 6 ! can u help me please?
I tried with strrep(data,',','.') but it doesnt work !

Since you are using commas, for your radix point, you will want to first load in the entire file as a string, replace the , with . and then you can use str2num to convert the entire file to a numeric array
% Read the entire file into memory
fid = fopen(loaddata, 'rb');
contents = fread(fid, '*char')';
fclose(fid);
% Replace `,` with `.`
contents = strrep(contents, ',', '.');
% Now convert to numbers
data = str2num(contents);

Related

Save the data in a form of three columns in text files

This function reads the data from multiple mat files and save them in multiple txt files. But the data (each value) are saved one value in one column and so on. I want to save the data in a form of three columns (coordinates) in the text files, so each row has three values separated by space. Reshape the data before i save them in a text file doesn't work. I know that dlmwrite should be modified in away to make newline after three values but how?
mat = dir('*.mat');
for q = 1:length(mat)
load(mat(q).name);
[~, testName, ~] = fileparts(mat(q).name);
testVar = eval(testName);
pos(q,:,:) = testVar.Bodies.Positions(1,:,:);
%pos=reshape(pos,2,3,2000);
filename = sprintf('data%d.txt', q);
dlmwrite(filename , pos(q,:,:), 'delimiter','\t','newline','pc')
end
My data structure:
These data should be extracted from each mat file and stored in the corresponding text files like this:
332.68 42.76 42.663 3.0737
332.69 42.746 42.655 3.0739
332.69 42.75 42.665 3.074
A TheMathWorks-trainer once told me that there is almost never a good reason nor a need to use eval. Here's a snippet of code that should solve your writing problem using writematrix since dlmwrite is considered to be deprecated.
It further puts the file-handling/loading on a more resilient base. One can access structs dynamically with the .(FILENAME) notation. This is quite convenient if you know your fields. With who one can list variables in the workspace but also in .mat-files!
Have a look:
% path to folder
pFldr = pwd;
% get a list of all mat-files (returns an array of structs)
Lst = dir( fullfile(pFldr,'*.mat') );
% loop over files
for Fl = Lst.'
% create path to file
pFl = fullfile( Fl.folder, Fl.name );
% variable to load
[~, var2load, ~] = fileparts(Fl.name);
% get names of variables inside the file
varInfo = who('-file',pFl);
% check if it contains the desired variables
if ~all( ismember(var2load,varInfo) )
% display some kind of warning/info
disp(strcat("the file ",Fl.name," does not contain all required varibales and is therefore skipped."))
% skip / continue with loop
continue
end
% load | NO NEED TO USE eval()
Dat = load(pFl, var2load);
% DO WHATEVER YOU WANT TO DO
pos = squeeze( Dat.(var2load)(1,:,1:2000) );
% create file name for text file
pFl2save = fullfile( Fl.folder, strrep(Fl.name,'.mat','.txt') );
writematrix(pos,pFl2save,'Delimiter','\t')
end
To get your 3D-matrix data into a 2D matrix that you can write nicely to a file, use the function squeeze. It gets rid of empty dimensions (in your case, the first dimension) and squeezes the data into a lower-dimensional matrix
Why don't you use writematrix() function?
mat = dir('*.mat');
for q = 1:length(mat)
load(mat(q).name);
[~, testName, ~] = fileparts(mat(q).name);
testVar = eval(testName);
pos(q,:,:) = testVar(1,:,1:2000);
filename = sprintf('data%d.txt', q);
writematrix(pos(q,:,:),filename,'Delimiter','space');
end
More insight you can find here:
https://www.mathworks.com/help/matlab/ref/writematrix.html

how to save multiple Cell array values in one .csv file

I have been working on making a database which contains images and their preset values and other important parameters. But unfortunately, I'm not being able to save the initial data of say 10 images in one .csv file. I have made the code that runs fine with creating .csv file but saving the last value and overwriting all the previous values. I gave also once modified that is comment down in the code using sprintf but it make .csv file for every iteration separately. But i want to make one .csv file containing 7 column with all the respective values.
My code is below and output of my code is attached Output.
Please someone guide me how to make single .csv file with 10 values for instance (could be increased to hundreds in final database) to save in 1 .csv file.
clc
clear all
myFolder = 'C:\Users\USER\Desktop\PixROIDirectory\PixelLabelData_1';
filePattern = fullfile(myFolder, '*.png'); % Change to whatever pattern you need
theFiles = dir(filePattern);
load('gTruthPIXDATA.mat','gTruth')
gTruth.LabelDefinitions;
for i=1:10
%gTruth.LabelData{i,1};
baseFileName = theFiles(i).name;
fullFileName = fullfile(myFolder, baseFileName);
fprintf(1, 'Now reading %s\n', fullFileName);
imageArray = imread(fullFileName);
oUt = regionprops(imageArray,'BoundingBox');
Y = floor(oUt.BoundingBox);
X_axis = Y(1);
Y_axis = Y(2);
Width = Y(3);
Height = Y(4);
CLASS = gTruth.LabelDefinitions{1,1};
JPG = gTruth.DataSource.Source{i,1};
PNG = gTruth.LabelData{i,1};
OUTPUT = [JPG X_axis Y_axis Width Height CLASS PNG]
% myFile = sprintf('value%d.csv',i);
% csvwrite(myFile,OUTPUT);
end
Try fprintf (https://www.mathworks.com/help/matlab/ref/fprintf.html).
You will need to open your output file to be written, then you can append lines to it through each iteration
Simple example:
A = [1:10]; % made up a matrix of numbers
fid = fopen('test.csv','w'); % open a blank csv and set as writable
for i = 1:length(A) % loop through the matrix
fprintf(fid,'%i\n',A(i)); % print each integer, then a line break \n
end
fclose(fid); % close the file for writing

Reading data from a Text File into Matlab array

I am having difficulty in reading data from a .txt file using Matlab.
I have to create a 200x128 dimension array in Matlab, using the data from the .txt file. This is a repetitive task, and needs automation.
Each row of the .txt file is a complex number of form a+ib, which is of form a[space]b. A sample of my text file :
Link to text file : Click Here
(0)
1.2 2.32222
2.12 3.113
.
.
.
3.2 2.22
(1)
4.4 3.4444
2.33 2.11
2.3 33.3
.
.
.
(2)
.
.
(3)
.
.
(199)
.
.
I have numbers of rows (X), inside the .txt file surrounded by brackets. My final matrix should be of size 200x128. After each (X), there are exactly 128 complex numbers.
Here is what I would do. First thing, delete the "(0)" types of lines from your text file (could even use a simple shells script for that). This I put into the file called post2.txt.
# First, load the text file into Matlab:
A = load('post2.txt');
# Create the imaginary numbers based on the two columns of data:
vals = A(:,1) + i*A(:,2);
# Then reshape the column of complex numbers into a matrix
mat = reshape(vals, [200,128]);
The mat will be a matrix of 200x128 complex data. Obviously at this point you can put a loop around this to do this multiple times.
Hope that helps.
You can read the data in using the following function:
function data = readData(aFilename, m,n)
% if no parameters were passed, use these as defaults:
if ~exist('aFilename', 'var')
m = 128;
n = 200;
aFilename = 'post.txt';
end
% init some stuff:
data= nan(n, m);
formatStr = [repmat('%f', 1, 2*m)];
% Read in the Data:
fid = fopen(aFilename);
for ind = 1:n
lineID = fgetl(fid);
dataLine = fscanf(fid, formatStr);
dataLineComplex = dataLine(1:2:end) + dataLine(2:2:end)*1i;
data(ind, :) = dataLineComplex;
end
fclose(fid);
(edit) This function can be improved by including the (1) parts in the format string and throwing them out:
function data = readData(aFilename, m,n)
% if no parameters were passed, use these as defaults:
if ~exist('aFilename', 'var')
m = 128;
n = 200;
aFilename = 'post.txt';
end
% init format stuff:
formatStr = ['(%*d)\n' repmat('%f%f\n', 1, m)];
% Read in the Data:
fid = fopen(aFilename);
data = fscanf(fid, formatStr);
data = data(1:2:end) + data(2:2:end)*1i;
data = reshape(data, n,m);
fclose(fid);

How to read numbered sequence of .dat files into MATLAB

I am trying to load a numbered sequence of ".dat" named in the form a01.dat, a02.dat... a51.dat into MATLAB. I used the eval() function with the code below.
%% To load each ".dat" file for the 51 attributes to an array.
a = dir('*.dat');
for i = 1:length(a)
eval(['load ' a(i).name ' -ascii']);
end
attributes = length(a);
I ran into problems with that as I could not easily manipulate the data loaded with the eval function. And I found out the community is strongly against using eval. I used the csvread() with the code below.
% Scan folder for number of ".dat" files
datfiles = dir('*.dat');
% Count Number of ".dat" files
numfiles = length(datfiles);
% Read files in to MATLAB
for i = 1:1:numfiles
A{i} = csvread(datfiles(i).name);
end
The csvread() works for me but it reads the files but messes up the order when it reads the files. It reads a01.dat first and then a10.dat and a11.dat and so on instead of a01.dat, a02.dat... The contents of each files are signed numbers. Some are comma-delimited and single column and this is an even split. So a01.dat's contents are comma-delimited and a02.dat's content are in a single column.
Please how do I handle this?
Your problem seems to be sorting of the files. Drawing on a question on mathworks, this should help you:
datfiles = dir('*.mat');
name = {datfiles.name};
[~, index] = sort(name);
name = name(index);
And then you can loop with just name:
% Read files in to MATLAB
for i = 1:1:numfiles
A{i} = csvread(name{i});
end

convert ascii .dat files to .xml using Matlab (or any other software)

I have a set of ascii files with the extension .dat and I need to convert them into a set of .xml files.
Is there anyway to do this with Matlab or any other software.
This is one of the files that I need to convert:
https://docs.google.com/open?id=0B1GI9KuZUKX3TDFCZDVTbzdINUE
I've used XML4MAT in the past. It will handle the data conversion into and out of an XML format, but doesn't quite handle actually reading and writing the XML file, so you have to add a little glue code. The sequence is:
Read the dat file into one variable in MATLAB (here I use the variable name Data). It looks like your file is essentially a table of numbers so that is easy.
Use DumpToXML.m and LoadFromXML.m as the glue code to the XML4MAT package that you'll download separately.
% function DumpToXML(XMLFileName, Data)
function DumpToXML(XMLFileName, Data)
% Generate the text of the XML file.
XMLData = ['<root>' 10];
XMLData = [XMLData mat2xml(Data, 'Data', 1)];
XMLData = [XMLData '</root>' 0];
% Now output the data.
fid = fopen(XMLFileName, 'w');
fprintf(fid, '%s', XMLData);
fclose(fid);
end
% function LoadFromXML(XMLFileName)
function Data = LoadFromXML(XMLFileName)
% Open the XML file.
fid = fopen(XMLFileName, 'r');
if(fid <= 0)
error(['Cannot open XML file ' XMLFileName]);
end
XMLData = fscanf(fid, '%c', inf);
fclose(fid);
% Now get the Data tag.
DataStartIndex = findstr(XMLData, '<Data');
% Now find the end.
DataEndIndex = findstr(XMLData, '</Data>');
% Extract the strings for this two variable from the string
% containing the loaded XML file.
XMLData = XMLData(DataStartIndex:DataEndIndex+6);
% And turn it back into a variable.
Data = xml2mat(XMLData);
end
I don't think Matlab is the weapon of choice for that.
I'd advocate for Python since there are nice XML packages such as lxml. You should be able to parse the dat file easily with open() and readlines().