I have a program that loads data from a .txt file and performs some curve fitting. The input file name for this example is experiment09.txt.
After processing I want to save a variable with the same input filename but appended with something like _fit. So my saved workspace variable in this case would be experiment09_fit.txt.
I have gotten this far in MATLAB:
buf = length(filename)
saveName = filename(1:buf-7)
which gives me a saveName of experiment09 but I am at a loss as to how to add my chosen string on the end to make it experiment09_fit. Once I have a valid save name I will then just call
save(saveName, 'fittedValue', '-ASCII');
Help would be greatly appreciated.
What about this:
filename = 'experiment09.txt';
[pathstr, basename, ext] = fileparts(filename);
outname = [basename, '_fit', ext]; % will give 'experiment09_fit.txt'
Also use string concatenation for adding additional names to string variables.
For example,
filename = 'experiment09.txt';
[pathstr, name, ext] = fileparts(filename);
outputName1 = strcat(name,'_fit.');
outputName = strcat(outputName1,ext);
Related
this question about matlab:
i'm running a loop and each iteration a new set of data is produced, and I want it to be saved in a new file each time. I also overwrite old files by changing the name. Looks like this:
name_each_iter = strrep(some_source,'.string.mat','string_new.(j).mat')
and what I#m struggling here is the iteration so that I obtain files:
...string_new.1.mat
...string_new.2.mat
etc.
I was trying with various combination of () [] {} as well as 'string_new.'j'.mat' (which gave syntax error)
How can it be done?
Strings are just vectors of characters. So if you want to iteratively create filenames here's an example of how you would do it:
for j = 1:10,
filename = ['string_new.' num2str(j) '.mat'];
disp(filename)
end
The above code will create the following output:
string_new.1.mat
string_new.2.mat
string_new.3.mat
string_new.4.mat
string_new.5.mat
string_new.6.mat
string_new.7.mat
string_new.8.mat
string_new.9.mat
string_new.10.mat
You could also generate all file names in advance using NUM2STR:
>> filenames = cellstr(num2str((1:10)','string_new.%02d.mat'))
filenames =
'string_new.01.mat'
'string_new.02.mat'
'string_new.03.mat'
'string_new.04.mat'
'string_new.05.mat'
'string_new.06.mat'
'string_new.07.mat'
'string_new.08.mat'
'string_new.09.mat'
'string_new.10.mat'
Now access the cell array contents as filenames{i} in each iteration
sprintf is very useful for this:
for ii=5:12
filename = sprintf('data_%02d.mat',ii)
end
this assigns the following strings to filename:
data_05.mat
data_06.mat
data_07.mat
data_08.mat
data_09.mat
data_10.mat
data_11.mat
data_12.mat
notice the zero padding. sprintf in general is useful if you want parameterized formatted strings.
For creating a name based of an already existing file, you can use regexp to detect the '_new.(number).mat' and change the string depending on what regexp finds:
original_filename = 'data.string.mat';
im = regexp(original_filename,'_new.\d+.mat')
if isempty(im) % original file, no _new.(j) detected
newname = [original_filename(1:end-4) '_new.1.mat'];
else
num = str2double(original_filename(im(end)+5:end-4));
newname = sprintf('%s_new.%d.mat',original_filename(1:im(end)-1),num+1);
end
This does exactly that, and produces:
data.string_new.1.mat
data.string_new.2.mat
data.string_new.3.mat
...
data.string_new.9.mat
data.string_new.10.mat
data.string_new.11.mat
when iterating the above function, starting with 'data.string.mat'
I am new to matlab and image analysis. I would really appreciate some insight/help into the following problem. I am trying to rename images (jpg) in a folder that have a random name into specific (new) names. I made the an excel file with two columns the first column contains the old names and the second column the new names. I found the next code on stack overflow (Rename image file name in matlab):
dirData = dir('*.jpg'); %# Get the selected file data
fileNames = {dirData.name}; %# Create a cell array of file names
for iFile = 1:numel(fileNames) %# Loop over the file names
newName = sprintf('image%05d.jpg',iFile); %# Make the new name
movefile(fileNames{iFile},newName); %# Rename the file
end
The code gives all the photos a new name based on the old one but that is not what I want, the new names I use are not linked to the old ones. I tried the following code :
g= xlsread('names.xlsx') % names.xlsx the excel file with old and new names
for i=1:nrows(g)
image=open(g(i,1));
save(g(i,2),image);
end
It doesn't work. I get the error message :using open (line 68)
NAME must contain a single string. I don't think open is the right function to use.
Thank you !
How about this:
% Get the jpeg names
dir_data = dir('*.jpg');
jpg_names = {dir_data.name};
% Rename the files according to the .xlsx file
[~,g,~] = xlsread('names.xlsx'); % Thanks to the post of Sean
old_names = g(:,1);
new_names = g(:,2);
for k = 1:numel(old_names)
% check if the file exists
ix_file = strcmpi(old_names{k}, jpg_names);
if any(ix_file)
movefile(old_names{k}, new_names{k});
end;
end;
It seems like g = xlsread(file) reads only numeric data from file (see here). The third output argument of xlsread returns raw data including strings; does the following work? (i don't have excel and can't test it)
[~, ~, g] = xlsread('names.xlsx')
for i = 1:nrows(g)
movefile(g{i,1}, g{i,2})
end
I'm recording a sound and using wavwrite to save the wav file, but I need to save it in a specific folder in C:, such as in c:\Users\soundwav.
Here is an excerpt from my wavwrite code:
data(:,s)=getdata(ai,44100);
y = [y; data]
format shortg
c = clock;
fix(c);
a=num2str(c);
year=strcat(a(1),a(2),a(3),a(4),a(5));
month=strcat(a(19),a(20));
day=strcat(a(34),a(35));
hour=strcat(a(48),a(49));
min=strcat(a(63),a(64));
sec=strcat(a(74),a(75));
name=strcat(year,'-',month,'-',day,'-',hour,'-',min,'-',sec);
wavwrite(data,name);
You need to cd the path while saving it. I have included a line that concatenates the full path with name variable and then saves it.
data(:,s)=getdata(ai,44100);
y = [y; data]
format shortg
c = clock;
fix(c);
a=num2str(c);
year=strcat(a(1),a(2),a(3),a(4),a(5));
month=strcat(a(19),a(20));
day=strcat(a(34),a(35));
hour=strcat(a(48),a(49));
min=strcat(a(63),a(64));
sec=strcat(a(74),a(75));
name=strcat(year,'-',month,'-',day,'-',hour,'-',min,'-',sec);
name = strcat('c:\Users\soundwav\', name);
wavwrite(data,name);
To select the folder in which to save your file, you can use uigetdir which allows you to select the folder; then you can add to it the filename you've built.
directoryname = uigetdir
You can also specify a starting folder
directoryname = uigetdir('c:\user\')
name = strcat(directoryname, '\', name);
Hope this helps.
I'm currently doing a program in Octave where I want the user to be able to insert the file that he wants to load. The files in question are .mat files and are loaded with
load ("filename.mat")
I was thinking about doing something like this:
file=input("Whats the file name: ")
load ("file")
But that didn't work...
Anyone got any tips?
That's likely because you need to input the file name enclosed in single quotation marks : 'filename'. (Note: I use MATLAB but that should work just the same in Octave).
As an alternative you can use inputdlg to request user input. It gives you much flexibility as you can add fields to the prompt such as the file extension or else.
Here is a simple example:
clear
clc
prompt = {'Enter file name'};
dlg_title = 'Input';
num_lines = 1;
def = {'Dummy file'};
answer = inputdlg(prompt,dlg_title,num_lines,def)
The prompt looks like this:
You can fetch the asnwer like so:
name = answer{1};
And finally add the extension to load the .mat file:
filename = strcat(name,'.mat')
S = load(filename)
To do it in one go with the file extension:
prompt = {'Enter file name'; 'Enter file extension'};
dlg_title = 'Input';
num_lines = 1;
def = {'Dummy file'; '.mat'};
answer = inputdlg(prompt,dlg_title,num_lines,def)
name = answer{1};
extension = answer{2};
filename = strcat(name,extension)
S = load(filename)
Hope that helps!
I used Benoit_11's method but changed it to input instead since inputdlg doesn't seem to work in Octave.
clear
clc
name=input('Enter the file name, without the file extension: ','s')
filename = strcat(name,'.mat')
S = load(filename)
I try to save the each step results into sequence format. i.e.
cm_clusters_2_00001.dat
cm_clusters_2_00002.dat
cm_clusters_2_00003.dat
.
.
.
cm_clusters_2_00020.dat
"particles_file_name" show me the required file name in correct format but when it save that file it write "particles_file_name" and that is why i am over writing my results under the same name.
Part of code which generate sequence names:
for kk= 1:20
if(kk<10)
file_number = ['0000' int2str(kk)];
elseif(kk>=10 && kk<100)
file_number = ['000' int2str(kk)];
elseif(kk>=100 && kk<1000)
file_number = ['00' int2str(kk)];
elseif(kk>=1000 && kk<10000)
file_number = ['0' int2str(kk)];
end
particles_file_name = ['cm_clusters_2_' file_number '.dat'];
save ('particles_file_name')
end;
any body suggest me the the correct way how to save these file so its not over written under the same name. As code show the correct name
particles_file_name = ['cm_clusters_2_' file_number '.dat'];
but Save it wrong.
You need to change:
save('particles_file_name')
to
save(particles_file_name)
particles_file_name is your variable with the changing file name, so you need to pass it directly to the save command. What you are doing instead is passing a string 'particles_file_name' which has no relation whatsoever with the variable particles_file_name.