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).
Related
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
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
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(...);
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.
I have a directory that contains several folders. Each of these folders contains several images.
If we suppose that we have a directory that contains images, I know how to read these images (see my code below); If we suppose that these images are placed in subdirectories in this directory, then I don't know how to edit my code.
directory = 'my_direct';
dnames1={directory};
c{1} = dir(dnames1{1}); % struct array with 5 fileds (name, isdir,...)
if length(c{1}>0)
if c{1}(1).name =='.'
c{1} = c{1}(3:end); %ignore the '.' and '..'
end
end
for k = 1: length(c{1})
image= double(imread([dnames{1} '/' h{1}(L).name]))./255;
end
assuming that you want to go inside each sub-directory and read the images
Root_directory='The directory location';
sub_directories=dir(Root_directory);
sub_directories(1,2)=[]; % to remove . and ..
for sub_dir_index=1:length(sub_directories)
images=dir(fullfile(Root_directory,sub_directories(sub_dir_index).name));
the rest of your code
end
You can use this code for reading multiple images, all you should know is the path to that directory. Just write the path and the code will read your images according to the pattern you stored them. I hope you will find it useful.
myFolder = 'path';
if ~isdir(myFolder)
errorMessage = sprintf('Error: The following folder does not exist:\n%s', myFolder);
uiwait(warndlg(errorMessage));
return;
end
filePattern = fullfile(myFolder, '*.jpg');
jpegFiles = dir(filePattern);
for i = 1:length(jpegFiles)
baseFileName = jpegFiles(i).name;
fullFileName = fullfile(myFolder, baseFileName);
fprintf(1, 'Now reading %s\n', fullFileName);
Input_image = imread(fullFileName);
end
If you have the R2014b release of MATLAB with the Computer Vision System Toolbox, you can use the imageSet object:
imgSets = imageSet('my_direct','recursive')
imgSets will be an array of imageSet objects, each of which contains the paths to all image files in the sub-directories of my_direct. You can then read the j-th image from the i-th sub-directory as follows:
im = read(imgSets(i), j);