I wanted to create a feature vector for training dataset and wanted to store all feature as rows in the.mat file. The .mat file must be in the form Feature Vector. I am able to extract Feature of 1 image and store it in excel file or .mat file but not able to extract all image feature and store it in .mat file. Can anyone knows this?
Its something like appending the same variables in the same .mat file. I have tried
save('feat.mat','feature','-append');
Where 'feature' is an array
feature = [mydata, stats{k}];
I have a folder which contains images who's feature I wanted to extract and store as training dataset. Any help will be appreciated.
the code was rectified.
stats = graycoprops(GLCM_values{'contrast','homogeneity','Correlation','Energy'});
stats was a structure so converted into the array using
features=struct2array(stats);
and was able to save the features
Related
I am trying to extract a specific layer from multiple ( > 4000 ) HDF5 files. I used the code below. It worked, but when I tried to load the new saved files, they were not recognized as HDF5. Help would be highly appreciated.
files=dir('C:\OLD_GPM\*.HDF5') % Open dataset
for j = 1:numel(files)
r = h5read(files(j).name,'/Grid/precipitationCal');% Read the correct layer "Precipitation calibrated mm/hr"
save([''C:\New_GPM\' files(j).name],'r'); % save this layer
end
Only mat-file version 7.3 are HDF5 files, all older versions use another format. Use save(['C:\New_GPM\' files(j).name],'r','-v7.3'); to enforce writing an HDF5 file.
I have large .bin files (10GB 60GB) that I want to import to MATLAB; each binary file represents the output of two sensors, thus there are too columns of data. Here is a more manageable sized example of my data.
You will notice that there is a .txt version of the data; I need to upload the .bin files directly to MATLAB, I can't use the .txt version because it takes hours to convert with larger files.
The problem I have is that the .bin file has header information that I can't seem to interpret properly, and thus I cannot extract the data in MATLAB every time I try I seem to get gibberish values.
This is all the information I have about the binary header:
Loading Labview Binary Data into Matlab
LabVIEW Data Logger: Binary Header File Format
Any help/advice would be much appreciated I have been trying to solve this problem for days now.
P.S. Someone has already written a function to solve this problem but it does not seem to work with my binary data (could be something to do with the dimensions/size of my data): http://www.mathworks.co.uk/matlabcentral/fileexchange/27195-load-labview-binary-data
Below is the code that I am using to import my data, I believe that that d1 and d2 are the dimensions of my binary data. D2 is probably incorrect for the example file in the dropbox because it has been truncated.
The problem I have is that the code extracts my data and I know it is correct because I can check it with the .txt file (also in the drop box) however there are seaming random bad values between the good data points. These bad values result from the following strings following strings: "NI_ChannelName", "Sensor A", "Sensor B", "NI_UnitDescription", and "Volts" scatted throughout the binary file.
clear all
clc
fname = 'RTL5_57.bin';
fid = fopen(fname,'r','ieee-be');
d1 = fread(fid,4);
trash=fread(fid,2,'double');
d2 = fread(fid,4);
trash=fread(fid,1,'double');
data=fread(fid,'double');
I suppose you will need to change the data-format. See Matlab help.
https://decibel.ni.com/content/docs/DOC-39038
Scope:
1) Write a binary file in matlab and read into labview. 2) Write a binary file in labview and read into matlab.
Background:
IMPORTANT:
You must know (3) things about the binary data in the file before you can read the data:
1) what binary format (precision) was used to store the data
2) the exact number of values in the file to read.
3) Endianness
There is no row or column in binary files. Think of a long row/or a long column that needs to be mapped to a 2D array.
Resources on data in binary format.
http://cse.unl.edu/~sincovec/Matlab/Lesson%2024/Binary/CS211%20Lesson%2024%20-%20Binary%20File%20Input-Output.htm
I have a data file having 50 2-D data points written in Notepad. I want to use it in clustering algorithm to cluster these 50 points. How can I import this file? Is there any other way to use it in program?
You can save the data as a .csv file or you can save it to an excel spreadsheet and use xlsread(). See here for more info: http://www.mathworks.com/help/techdoc/ref/xlsread.html
For the .csv case, this post should prove helpful: Fastest way to import CSV files in MATLAB
Imagine you had the following data:
X = [randn(100,2)-1 ; randn(100,2)];
save data.mat X
Then its as simple as doing:
%# load data from MAT-file
load data.mat
%# cluster into K=2 clusters
C = kmeans(X,2);
%# show cluster assignment
gscatter(X(:,1), X(:,2), C)
It depends how you have formatted the data file. You say it is saved on notepad but that is not too helpful. Depending on what you have used as the data delimiter you can import the datafile into an array using the dlmread function. For example if your file is called filename.dat and have used a ; character to separate each data item within this file you could read the data into a matrix A using
A = dlmread("filename.dat",';');
I would suggest reading the help documentation on the dlmread function in matlab.
I am trying to load feature vectors into classifiers such as a k-nearest neighbors classifier.
I have my code for GLCM, so I get contrast, correlation, energy, homogeneity in numbers (feature vectors).
My question is, how can I save every set of feature vectors from all the training images? I have seen somewhere that people had a .set file to load into classifiers (may be it is a special case for the particular classifier toolbox).
load 'mydata.set';
for example.
I suppose it does not have to be a .set file.
I'd just need a way to store all the feature vectors from all the training images in a separate file that can be loaded.
I've google,
and I found this that may be useful
but I am not entirely sure.
Thanks for your time and help in advance.
Regards.
If you arrange your feature vectors as the columns of an array called X, then just issue the command
save('some_description.mat','X');
Alternatively, if you want the save file to be readable, say in ASCII, then just use this instead:
save('some_description.txt', 'X', '-ASCII');
Later, when you want to re-use the data, just say
var = {'X'}; % <-- You can modify this if you want to load multiple variables.
load('some_description.mat', var{:});
load('some_description.txt', var{:}); % <-- Use this if you saved to .txt file.
Then the variable named 'X' will be loaded into the workspace and its columns will be the same feature vectors you computed before.
You will want to replace the some_description part of each file name above and instead use something that allows you to easily identify which data set's feature vectors are saved in the file (if you have multiple data sets). Your array of feature vectors may also be called something besides X, so you can change the name accordingly.
I have 20 text files each containing a vector of size 180. How can I access each text file and assign the vector to a variable?
If you want to do it manually use Import Data under File (or use uiimport).
If you want to automate it use fid = fopen(filename) and then use var = textscan(fid, 'format') where format depends on how your vectors are structured. Spend some time reading doc textscan and doc fopen everything you probably need to know is in those two files. If your data is nicely structured look at doc importdata.