I want to save a matrix (e.g. "PTX_Data_Raw.mat") in another folder (e.g. Temp folder). I have written below code:
mkdir('D:\Projects\ProgrammingPart\Method2_FinalApproved\8-congruent','Temp');
filename=('D:\Projects\ProgrammingPart\Method2_FinalApproved\8-congruent\Temp');
save(filename,'PTX_Data_Raw.mat');
but it didn't work. Does anybody can help me for solving this problem?
THX
Going with your comments, you are using save wrong. The first parameter is the filename you want to call the MAT file and second parameter and onwards are the variables you want to save.
Therefore, you need to make sure filename contains the entire filename, including the path followed by the actual name of the MAT file you want. After, the second parameter is PTX_Data - the name of the matrix you want to save.
mkdir('D:\Projects\ProgrammingPart\Method2_FinalApproved\8-congruent','Temp');
%// Change
filename=('D:\Projects\ProgrammingPart\Method2_FinalApproved\8-congruent\Temp\PTX_Data_Raw.mat');
save(filename,'PTX_Data'); %// Change
Related
I would like to know how I can save the matlab output files (i.e. matlab workplace variables), by including original file name.
e.g. I open a file (filename.mat) with load filename.mat. Then I run a code to do calculation and I get some workplace variables (e.g. flow, pressure). I want to save those variables as filename_flow.mat and filename_pressure.mat.
I will use the same code on different filename, so I would like to know how I can save my variables as mentioned above (i.e. including the original file's name)?
FileToBeLoaded = 'filename.mat';
[pathstr,filename,ext] = fileparts(FileToBeLoaded)
load([filename ext]);
%// calculate stuff
FlowVariable = %// some calculation
save([filename '_flow'],FlowVariable)
The same of course works for other names as well. You pull apart the original file name to its actual name and extension, and use the original name, add something (_flow in this case) and save that. The default of MATLAB is already to save to a .mat file, so that's taken care of automatically.
I am somewhat new to MATLAB and am trying to set up a changing file path in a loop to go into a series of folders and grab image files from each folder. I'm not sure if the problem is with the concatenated parts of the path itself, or with the wildcard search I am using.
I've used similar changing file paths before that have worked, but this one is giving me a "Index exceeds matrix dimensions" error. I thought it was the '*' element that was problematic (similar concatenated paths have worked for me, but only when I specify a file extension or part of a file name), but I am trying to grab DICOM files that do not have any extension, which might make it difficult.
The line within the for loop is as follows:
inputs{1, crun} = cellstr(spm_select('FPList'[allinput,'T1Rawunzip',filesep,OrderForDicoms3{crun,1}],'*'));
I've tried different ways of specifying this--using spm_select, not using spm_select, using commas instead of filesep or vice versa, but nothing has worked.
Any advice would be very much appreciated.
(for reference:
crun is the counter the moves the loop forward, 'allinput' is a previously-specified path, OrderForDicoms3 is a .mat file with a list of folder names that are being individually concatenated to the path each time the loop runs)
Thanks!
-Victoria
I can tell you the most general approach of grabbing files from a folder. If you specify the input folder through uigetdir, then all the files can be grabbed using dir command:
folder = uigetdir;
files = dir(folder);
for i =1:length(files)
if(~files.isdir())
filename = fullfile(folder, files(i).name);
% ... read in the data %
end
end
You can always do it for multiple levels.
I tried to save my file using the command window in Matlab. Unfortunately it replaced my file with a new file. And now I am unable to get it back.
It's probably easy, but I am new to using the command window in Matlab.
You are out of luck on this one. Saving to a file will irretrievably overwrite any existing file with that name unless you specify otherwise with the -append option. In the future, if you have a data set that is important because it is either not reproducable or because it takes a long time to generate it, I would recommend either backing it up or saving it with a timestamp. This is one example:
function save_t(name,varargin)
save(sprintf('%s-%d',name,time),clock*[1e8 1e6 1e4 1e2 1 0].',varargin{:});
end
Save this to a file in you matlab path named "save_t.m" and then you can simply call it just like you would call the save function, but now it will add on a timestamp.
save_t filename
This will help to ensure that you don't accidentally overwrite an existing file.
i'm trying to load a mat file from a subdirectory using the following code:
% filename_str is read from a text file
directoryname_str = "./data";
f = fullfile(directoryname_str, filename_str);
load(f);
when i run this sequence, load says it can't find the file...but when i copy or type the relative path and the file name by hand into an active octave session, everything works like a champ with no errors.
i assume this has something to do with how octave searches for mat files? if so, what's the correct environment variable or function call i need to make in order for this code to work?
thanks!
Are you sure that what you put into the variable f is the same as what you input manually in octave?
Are you also in the same directory? Because you're specifying relative paths, this should be the case.. you can get the current directory octave is in with pwd
And last of all, you can double check file existence in octave itself using exist
exist(f,'file')
If this returns false, there's definitely something wrong with your current directory, are something's very weird going on..
I want to load specific column form .mat file already exist in the work space after I load it how should I write then ?
You can access part of a variable saved in a MAT file using MATFILE constructor (available since R2011b). Check my answer to another similar question.
For example, if you have matrix a saved in matlab.mat file you constract the matfile object as
matObj = matfile('matlab.mat');
Then you can access 2nd column like x = matObj.a(:,2);.