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

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

Related

Matlab: Error using readtable (line 216) Input must be a row vector of characters or string scalar

I gave the error Error using readtable (line 216) Input must be a row vector of characters or string scalar when I tried to run this code in Matlab:
clear
close all
clc
D = 'C:\Users\Behzad\Desktop\New folder (2)';
filePattern = fullfile(D, '*.xlsx');
file = dir(filePattern);
x={};
for k = 1 : numel(file)
baseFileName = file(k).name;
fullFileName = fullfile(D, baseFileName);
x{k} = readtable(fullFileName);
fprintf('read file %s\n', fullFileName);
end
% allDates should be out of the loop because it's not necessary to be in the loop
dt1 = datetime([1982 01 01]);
dt2 = datetime([2018 12 31]);
allDates = (dt1 : calmonths(1) : dt2).';
allDates.Format = 'MM/dd/yyyy';
% 1) pre-allocate a cell array that will store
% your tables (see note #3)
T2 = cell(size(x)); % this should work, I don't know what x is
% the x is xlsx files and have different sizes, so I think it should be in
% a loop?
% creating loop
for idx = 1:numel(x)
T = readtable(x{idx});
% 2) This line should probably be T = readtable(x(idx));
sort = sortrows(T, 8);
selected_table = sort (:, 8:9);
tempTable = table(allDates(~ismember(allDates,selected_table.data)), NaN(sum(~ismember(allDates,selected_table.data)),size(selected_table,2)-1),'VariableNames',selected_table.Properties.VariableNames);
T2 = outerjoin(sort,tempTable,'MergeKeys', 1);
% 3) You're overwriting the variabe T2 on each iteration of the i-loop.
% to save each table, do this
T2{idx} = fillmissing(T2, 'next', 'DataVariables', {'lat', 'lon', 'station_elevation'});
end
the x is each xlsx file from the first loop. my xlsx file has a different column and row size. I want to make the second loop process for all my xlsx files in the directory.
did you know what is the problem? and how to fix it?
Readtable has one input argument, a filename. It returns a table. In your code you have the following:
x{k} = readtable(fullFileName);
All fine, you are reading the tables and storing the contents in x. Later in your code you continue with:
T = readtable(x{idx});
You already read the table, what you wrote is basically T = readtable(readtable(fullFileName)). Just use T=x{idx}

Plotting data from cell

I have multiple geopoint data inside of a (1x2) data cell. How can I plot all of this data onto one map within MATLAB?
I have tried to append before but obviously it isn't what I want. I'm really trying to understand the best method.
clear;
clc;
% Specify folder where the files live
myFolder = 'C:\Users\J87662\Desktop\GPX Data Files';
% Check to make sure folder exists. Warns user if doesn't.
if ~isdir(myFolder)
errorMessage = sprintf('Error: The following folder does not exist:\n%s', myFolder);
uiwait(warndlg(errorMessage));
return;
end
% Get a list of all files in the folder with the desired file name pattern.
theFiles = dir(fullfile(myFolder, '*.gpx')); % Using .gpx as the desired file type.
% Number of files in the folder
n = numel(theFiles);
data = cell(1,n);
for k=1:n
% Read each file
data{k} = gpxread(fullfile( myFolder, theFiles(k).name ));
baseFileName = theFiles(k).name;
fullFileName = fullfile(myFolder, baseFileName);
fprintf(1, 'Now reading %s\n', fullFileName);
end
When trying to use data(1,1).Latitude, I get the error "Struct contents reference from a non-struct array object."
Indexing into cell arrays requires the use of {} rather than (). Try data{1, 1}.Latitude instead (since you have only a single column, data{1}.Latitude should also work).

Read a value from multiple text files and write all into another file

I have a list of sub-folders and each sub-folder has a text file name called simass.txt. From each of the simass.txt files I extract a c{1}{2,3} cell data (as done in the code below) and write it to a file name features.txt in sequential form in single column.
I am facing a problem where at the end I only have a single value in features.txt, which I believe is due to the values being overwritten. I'm supposed to have 1000 values in features.txt since I have 1000 sub-folders.
What am I doing wrong?
clc; % Clear the command window.
workspace; % Make sure the workspace panel is showing.
format long g;
format compact;
% Define a starting folder wherever you want
start_path = fullfile(matlabroot, 'D:\Tools\Parameter Generation\');
% Ask user to confirm or change.
topLevelFolder = uigetdir(start_path);
if topLevelFolder == 0
return;
end
% Get list of all subfolders.
allSubFolders = genpath(topLevelFolder);
% Parse into a cell array.
remain = allSubFolders;
listOfFolderNames = {};
while true
[singleSubFolder, remain] = strtok(remain, ';');
if isempty(singleSubFolder)
break;
end
listOfFolderNames = [listOfFolderNames singleSubFolder];
end
numberOfFolders = length(listOfFolderNames)
% Process all text files in those folders.
for k = 1 : numberOfFolders
% Get this folder and print it out.
thisFolder = listOfFolderNames{k};
fprintf('Processing folder %s\n', thisFolder);
% Get filenames of all TXT files.
filePattern = sprintf('%s/simass.txt', thisFolder);
baseFileNames = dir(filePattern);
numberOfFiles = length(baseFileNames);
% Now we have a list of all text files in this folder.
if numberOfFiles >= 1
% Go through all those text files.
for f = 1 : numberOfFiles
fullFileName = fullfile(thisFolder, baseFileNames(f).name);
fileID=fopen(fullFileName);
c=textscan(fileID,'%s%s%s','Headerlines',10,'Collectoutput',true);
fclose(fileID);
%celldisp(c) % display all cell values
cellvalue=c{1}{2,3}
filePh = fopen('features.txt','w');
fprintf(filePh,cellvalue);
fclose(filePh);
fprintf(' Processing text file %s\n', fullFileName);
end
else
fprintf(' Folder %s has no text files in it.\n', thisFolder);
end
end
The problem is in the permission you use in fopen. From the documentation:
'w' - Open or create new file for writing. Discard existing contents, if any.
Which means you're discarding the contents every time, and you end up only having the last value. The fastest fix would be changing the permission to 'a', but I would suggest adding some changes to the code as follows:
Creating cellvalue before the loop, and read c{1}{2,3} into this new vector/cell array.
Perform the writing operation once, after cellvalue is fully populated.
cellvalue = cell(numberOfFiles,1);
for f = 1 : numberOfFiles
...
cellvalue{f} = c{1}{2,3};
end
fopen(...);
fprintf(...);
fclose(...);

frame to video conversion matlab

So I just started with image processing/computer vision in MATLAB.
So my first task is to convert a series of images(frames) into a video. So I went through online sources (MATLAB website more specifically) to get a way to do it.
So the one that I implemented is http://www.mathworks.com/help/matlab/examples/convert-between-image-sequences-and-video.html which solved the problem for me.
However, when I play it, the video seems jumpy in some places. Like it would bring a different frame in the middle and make the whole video jumpy for that split second. It happens a couple of places in the video.
Any anyone knows why this happens?
Thanks
PS below is the code I use:
myFolder = 'C:\Users\owner\Desktop\MATLAB GUI\Color\Color'; %Specify Directory
filePattern = fullfile(myFolder, '*.jpg') %identify jpg files
jpegFiles = dir(filePattern) %use dir to list jpg files
size = length(jpegFiles); % length of the size of the file
outputVideo = VideoWriter(fullfile(myFolder,'video1.avi'));
outputVideo.FrameRate = 30;
open(outputVideo);
for i = 1:length(jpegFiles) %load all the files in the directory
j = i; %%accumulating the number of jpegfiles into handles.j
baseFileName = jpegFiles(i).name;
fullFileName = fullfile(myFolder, baseFileName);
%fprintf(1, 'Now reading %s\n', fullFileName); %filename of image
imageArray = imread(fullFileName); %image being read
%imageArray = rgb2gray(imageArray);
imagecell{i} = imageArray; %storing the images in imagecells
writeVideo(outputVideo,imagecell{i});
end
close(outputVideo);
video1 = VideoReader(fullfile(myFolder,'video1.avi'));
mov(video1.NumberOfFrames) = struct('cdata',[],'colormap',[]);
for ii = 1:video1.NumberOfFrames
mov(ii) = im2frame(read(video1,ii));
end
set(gcf,'position', [150 150 video1.Width video1.Height])
set(gca,'units','pixels');
set(gca,'position',[0 0 video1.Width video1.Height])
image(mov(1).cdata,'Parent',gca);
axis off;
movie(mov,1,video1.FrameRate);
Given that there may be too many files to be renamed (padded with zeros) here is a quick function that will do it for you: you just need to provide the directory/folder where the images are stored, the padding (if less 100 files, then padding can be 2; if less than 1000 files, then padding can be 3; etc.), and a common pattern. The code assumes that there is a common pattern in each file (like 'frame' or 'image') that when removed, leaves just the number:
renameFiles(directory,padSize,fileNamePattern)
filePattern = fullfile(directory, '*.jpg') %identify jpg files
jpegFiles = dir(filePattern) %use dir to list jpg files
for k=1:size(jpegFiles)
% get the source file that will be moved/renamed
fileSrc = jpegFiles(k).name;
% get the parts of the file
[path,name,ext] = fileparts(fileSrc);
% where does the pattern fit in the name?
idx = strfind(name,fileNamePattern);
% remove the pattern from the name
if idx==0
% pattern does not exist in file so skip it
continue;
elseif idx==1
% pattern is at the beginning of name so remove it
frameNumberStr = name(length(fileNamePattern)+1:end);
else
% pattern is at the end of name so remove it
frameNumberStr = name(1:idx-1);
end
% get the number of digits
numDigits = length(frameNumberStr);
% create the new file name
paddedName = [fileNamePattern repmat('0',1,padSize-numDigits) frameNumberStr];
fprintf('%s\n',paddedName);
% only move if the destination is different
if strcmp(paddedName,name) ~= 1
% set the destination file
fileDest = fullfile(directory,[paddedName ext]);
% move the file
movefile(fileSrc, fileDest,'f');
end
end
end
An example - if all files have the common pattern of 'frame' and there are less than 1000 files, then run this function as
rename(pwd,3,'frame')
All files that were named as frame1.jpg or frame99.jpg are now named as frame001.jpg and frame099.jpg.
Hope this helps!
If you have the Computer Vision System Toolbox you can use the vision.VideoFileWriter object. You can simply feed images into its step() method one at a time, and they will be written to the video file as video frames. Note that the images must all be the same size and have the same data type.

Find which line of a .dat file MATLAB is working on

I have a MATLAB script that reads a line from a text file. Each line of the text file contains the filename of a CSV. I need to keep track of what line MATLAB is working on so that I can save the data for that line in a cell array. How can I do that?
To illustrate, the first few lines of my .dat file looks like this:
2006-01-003-0010.mat
2006-01-027-0001.mat
2006-01-033-1002.mat
2006-01-051-0001.mat
2006-01-055-0011.mat
2006-01-069-0004.mat
2006-01-073-0023.mat
2006-01-073-1003.mat
2006-01-073-1005.mat
2006-01-073-1009.mat
2006-01-073-1010.mat
2006-01-073-2006.mat
2006-01-073-5002.mat
2006-01-073-5003.mat
I need to save the variable site_data from each of these .mat files into a different cell of O3_data. Therefore, I need to have a counter so that O3_data{1} is the data from the first line of the text file, O3_data{2} is the data from the second line, etc.
This code works, but it's done without using the counter so I only get the data for one of the files I'm reading in:
year = 2006:2014;
for y = 1:9
flist = fopen(['MDA8_' num2str(year(y)) '_mat.dat']); % Open the list of file names - CSV files of states with data under consideration
nt = 0; % Counter will go up one for each file loaded
while ~feof(flist) % While end of file has not been reached
fname = fgetl(flist);
disp(fname); % Stores name as string in fname
fid = fopen(fname);
while ~feof(fid)
currentLine = fgetl(fid);
load (fname, 'site_data'); % Load current file. It is all the data for one site for one year
O3_data = site_data;
% Do other stuff
end
fclose(fid);
end
fclose(flist);
end
If I add the time index part, MATLAB is telling me that Subscript indices must either be real positive integers or logicals. nt is an integer so I don't know what I'm doing wrong. I need the time index so that I can have O3_data{i} in which each i is one of the files I'm reading in.
year = 2006:2014;
for y = 1:9
flist = fopen(['MDA8_O3_' num2str(year(y)) '_mat.dat']); % Open the list of file names - CSV files of states with data under consideration
nt = 0;
while ~feof(flist) % While end of file has not been reached
fname = fgetl(flist);
fid = fopen(fname);
while ~feof(fid)
currentLine = fgetl(fid);
nt = nt+1; % Time index
load (fname, 'site_data'); % Load current file. It is all the data for one site for one year
O3_data{nt} = site_data;
% Do other stuff
end
fclose(fid);
end
fclose(flist);
end
Try the following:
years = 2006:2014;
for y=1:numel(years)
% read list of filenames for this year (as a cell array of strings)
fid = fopen(sprintf('MDA8_O3_%d_mat.dat',years(y)), 'rt');
fnames = textscan(fid, '%s');
fnames = fnames{1};
fclose(fid);
% load data from each MAT-file
O3_data = cell(numel(fnames),1);
for i=1:numel(fnames)
S = load(fnames{i}, 'site_data');
O3_data{i} = S.site_data;
end
% do something with O3_data cell array ...
end
Try the following - note that since there is an outer for loop, the nt variable will have to be initialized outside of that loop so that we don't overwrite data from previous years (or previous j's). We can avoid the inner while loop since the just read file is a *.mat file and we are using the load command to load its single variable into the workspace.
year = 2006:2014;
nt = 0;
data_03 = {}; % EDIT added this line to initialize to empty cell array
% note also the renaming from 03_data to data_03
for y = 1:9
% Open the list of file names - CSV files of states with data under
% consideration
flist = fopen(['MDA8_O3_' num2str(year(y)) '_mat.dat']);
% make sure that the file identifier is valid
if flist>0
% While end of file has not been reached
while ~feof(flist)
% get the name of the *.mat file
fname = fgetl(flist);
% load the data into a temp structure
data = load(fname,'site_data');
% save the data to the cell array
nt = nt + 1;
data_03{nt} = data.site_data;
end
fclose(flist); % EDIT moved this in to the if statement
end
end
Note that the above assumes that each *.dat file contains a list of *.mat files as illustrated in your above example.
Note the EDITs in the above code from the previous posting.