I want to read the data of a file with size about 60 MB into matlab in some variables, but I get errors. This is my code:
clear all ;
clc ;
% Reading Input File
Dataz = importdata('leak0.lis');
%Dataz = load('leak0.lis');
for k = 1:1370
foundPosition = 1 ;
for i=1:size(Dataz,1)
strp = sprintf('I%dz=',k);
fprintf(strp);
findValue = strfind(Dataz{i}, strp) ;
if ~isempty(findValue)
eval_param = strp + '(foundPosition) = sscanf(Dataz{i},''%*c%*c%*f%*c%*c%f'') ;';
disp(eval_param);
% str(foundPosition) = sscanf(Dataz{i},'%*c%*c%*f%*c%*c%f') ;
eval(eval_param);
foundPosition = foundPosition + 1 ;
end
end
end
When I debugged it, I found out that the dataz is empty & so it doesn't proceed to next lines. I replace it with fopen, load & etc, but it didn't work.
From the Matlab help files, import data is likely failing because it doesn't understand your file format.
From the help files
Name and extension of the file to import, specified as a string. If importdata recognizes the file extension, it calls the MATLAB helper function designed to import the associated file format (such as load for MAT-files or xlsread for spreadsheets). Otherwise, importdata interprets the file as a delimited ASCII file.
For ASCII files and spreadsheets, importdata expects to find numeric
data in a rectangular form (that is, like a matrix). Text headers can
appear above or to the left of the numeric data, as follows:
Assuming that your .lis files actually have delimited text.
You should adjust the delimiter in the importdata call so that Matlab can understand your file.
filename = 'myfile01.txt';
delimiterIn = ' ';
headerlinesIn = 1;
A = importdata(filename,delimiterIn,headerlinesIn);
Related
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
Loading a well formatted and delimited text file in Matlab is relatively simple, but I struggle with a text file that I have to read in. Sadly I can not change the structure of the source file, so I have to deal with what I have.
The basic file structure is:
123 180 (two integers, white space delimited)
1.5674e-8
.
.
(floating point numbers in column 1, column 2 empty)
.
.
100 4501 (another two integers)
5.3456e-4 (followed by even more floating point numbers)
.
.
.
.
45 String (A integer in column 1, string in column 2)
.
.
.
A simple
[data1,data2]=textread('filename.txt','%f %s', ...
'emptyvalue', NaN)
Does not work.
How can I properly filter the input data? All examples I found online and in the Matlab help so far deal with well structured data, so I am a bit lost at where to start.
As I have to read a whole bunch of those files >100 I rather not iterate trough every single line in every file. I hope there is a much faster approach.
EDIT:
I made a sample file available here: test.txt (google drive)
I've looked at the text file you supplied and tried to draw a few general conclusions -
When there are two integers on a line, the second integer corresponds to the number of rows following.
You always have (two integers (A, B) followed by "B" floats), repeated twice.
After that you have some free-form text (or at least, I couldn't deduce anything useful about the format after that).
This is a messy format so I doubt there are going to be any nice solutions. Some useful general principles are:
Use fgetl when you need to read a single line (it reads up to the next newline character)
Use textscan when it's possible to read multiple lines at once - it is much faster than reading a line at a time. It has many options for how to parse, which it is worth getting to know (I recommend typing doc textscan and reading the entire thing).
If in doubt, just read the lines in as strings and then analyse them in MATLAB.
With that in mine, here is a simple parser for your files. It will probably need some modifications as you are able to infer more about the structure of the files, but it is reasonably fast on the ~700 line test file you gave.
I've just given the variables dummy names like "a", "b", "floats" etc. You should change them to something more specific to your needs.
function output = readTestFile(filename)
fid = fopen(filename, 'r');
% Read the first line
line = '';
while isempty(line)
line = fgetl(fid);
end
nums = textscan(line, '%d %d', 'CollectOutput', 1);
a = nums{1}(1);
b = nums{1}(2);
% Read 'b' of the next lines:
contents = textscan(fid, '%f', b);
floats1 = contents{1};
% Read the next line:
line = '';
while isempty(line)
line = fgetl(fid);
end
nums = textscan(line, '%d %d', 'CollectOutput', 1);
c = nums{1}(1);
d = nums{1}(2);
% Read 'd' of the next lines:
contents = textscan(fid, '%f', d);
floats2 = contents{1};
% Read the rest:
rest = textscan(fid, '%s', 'Delimiter', '\n');
output.a = a;
output.b = b;
output.c = c;
output.d = d;
output.floats1 = floats1;
output.floats2 = floats2;
output.rest = rest{1};
end
You can read in the file line by line using the lower-level functions, then parse each line manually.
You open the file handle like in C
fid = fopen(filename);
Then you can read a line using fgetl
line = fgetl(fid);
String tokenize it on spaces is probably the best first pass, storing each piece in a cell array (because a matrix doesn't support ragged arrays)
colnum = 1;
while ~isempty(rem)
[token, rem] = strtok(rem, ' ');
entries{linenum, colnum} = token;
colnum = colnum + 1;
end
then you can wrap all of that inside another while loop to iterate over the lines
linenum = 1;
while ~feof(fid)
% getl, strtok, index bookkeeping as above
end
It's up to you whether it's best to parse the file as you read it or read it into a cell array first and then go over it afterwards.
Your cell entries are all going to be strings (char arrays), so you will need to use str2num to convert them to numbers. It does a good job of working out the format so that might be all you need.
I need to extract the first value of the following code:
3.43099,70.8539,91.701,FAIL
The file has the '.sol' extension, but it can be read in notepad or Matlab.
I just want to know how to to read in all *.sol files in a folder and how to write the extracted value in a text file.
Thanks a lot, i would be grateful.
NEW
ita='"';
for i=1:size(z,2)
word_to_replace=input('Replace? ','s');
tik=input('Replacement? ','s');
coluna=input('Column? ');
files = dir('*.txt');
for i = 1:numel(files)
if ~files(i).isdir % make sure it is not a directory
contents = fileread(files(i).name);
fh = fopen(files(i).name,'w');
val=num2str(z(i,coluna));
word_replacement=strcat(tik,val,ita);
contents = regexprep(contents,'word_to_replace','word_replacement');
fprintf(fh,contents); % write "replaced" string to file
fclose(fh) % close out file
end
end
end
Many thanks
File extension does not make a difference as to what MATLAB can "read", use the fileread command to load in the file and parse its contents. You can then split on commas, since it looks like it is comma separated
files = dir('*.sol');
fh = fopen('outFile.txt','w');
for i = 1:numel(files)
if ~files(i).isdir % make sure it is not a directory
contents = fileread(files(i).name);
parts = regexp(contents,',','Split');
fprintf(fh,[parts{1},'\n']);
end
end
fclose(fh)
This should do what you want. It will find all files in the current directory with the .sol extension, loop through all of them, grab the first value, and write it out to a text file.
Find and replace
Finding and replacing is relatively simple as well. You can do the same looping, read the file contents, run a replacement, and then rewrite that out to the same file.
files = dir('*.sol');
for i = 1:numel(files)
if ~files(i).isdir % make sure it is not a directory
contents = fileread(files(i).name);
fh = fopen(files(i).name,'w'); % open handle to same file just read for overwriting
contents = regexprep(contents,'toReplace','replacement'); % do string replacement
fprintf(fh,contents); % write "replaced" string to file
fclose(fh) % close out file
end
end
I have a large text file (~3500 lines) which contains output data from an instrument. This consists of repeated entries from different measurements which are all formatted as follows:
* LogFrame Start *
variablename1: value
variablename2: value
...
variablename35: value
* LogFrame End *
Each logframe contains 35 variables. From these I would like to extract two, 'VName' and 'EMGMARKER' and put the associated values in columns in a matlab array, (i.e. the array should be (VName,EMGMARKER) which I can then associate with data from another output file which I already have in a matlab array. I have no idea where to start with this in order to extract the variables from this file, so hence my searches on the internet so far have been unsuccessful. Any advice on this would be much appreciated.
You could use textscan:
C = textscan(file_id,'%s %f');
Then you extract the variables of interest like this:
VName_indices = strcmp(C{1},'VName:');
VName = C{2}(VName_indices);
If the variable names, so 'VName' and 'EMGMARKER' , are always the same you can just read through the file and search for lines containing them and extract data from there. I don't know what values they contain so you might have to use cells instead of arrays when extracting them.
fileID = fopen([target_path fname]); % open .txt file
% read the first line of the specified .txt file
current_line = fgetl(fileID);
counter = 1;
% go through the whole file
while(ischar(current_line))
if ~isempty(strfind(current_line, VName))
% now you find the location of the white space delimiter between name and value
d_loc = strfind(current_line,char(9));% if it's tab separated - so \t
d_loc = strfind(current_line,' ');% if it's a simple white space
variable_name{counter} = strtok(current_line);% strtok returns everything up until the first white space
variable_value{counter} = str2double(strtok(current_line(d_loc(1):end)));% returns everything form first to second white space and converts it into a double
end
% same block for EMGMARKER
counter = counter+1;
current_line = fgetl(fileID);% next line
end
You do the same for EMGMARKER and you have cells containing the data you need.
Below is the code to convert .tim file to ascii file for one particular file. But what I need is to convert 500 files(.tim). I also need to save the .ascii file in SAME name as the .tim file name like below for all 500 files.
bin=fopen('file_01.tim','r');
ascii = fread(bin, [43,21000], 'float32');
data_values=ascii';
dlmwrite('file_01.xls', data_values, 'delimiter', '\t', ...
'precision', '%.6f','newline','pc');
Using a "for loop" to do the conversion and save the ascii file with the same name of the tim, was my first thought but I don't know how to that.
You can use dir to get a list of all the filenames in your folder and then proceed just as you have but using replacing 'file_01.tim' with [D(ii).name]
e.g.
D = dir('*.tim');
for ii = 1:size(D,1)
bin=fopen(D(ii).name,'r');
%your processing etc
savename = [strtok(D(ii).name,'.'), '.xls']; %Change the file ext from .tim to .xls
dlmwrite(savename, ...