I am reading a comma-separated text file into Matlab with the dataset() function. The variable names in the text file contain double quotes around the names. I am reading this file into Matlab, manipulating the data, and exporting to a separate text file. The issue is that I need the double quotes to remain around the variable names; however, Matlab removes them.
Is there a way I can tell Matlab to keep the quotes, or an easy way to replace the quotes before exporting? Thanks
Text file looks like this: ["Var1","Var2",....] - There is no issue with Matlab importing the file.
inputname = 'MyFile.TXT';
outputname = 'MyOutput.TXT';
rawinventory = dataset('File', inputname', 'Delimiter', ',',
'ReadVarNames', true);
rawinventory(1,1); %The Command Window shows the first entry and the
%header name without the double quotes.
temp_raw = dataset2cell(rawinventory(:,:));
% Perform some data Manipulation here
%........
edited_raw = cell2dataset(temp_raw(:,:));
export(edited_raw, 'File', outputname, 'Delimiter', ',');
I know that there may be better ways to run this code. My job is not as a developer or IT. I occasionally need to edit files used in other processes. Unfortunately, the process after this manipulation requires the double quotes around the variable names.
This function solves this issue. Place the .m file for the function in the same folder as the .m file with the code. https://www.mathworks.com/matlabcentral/fileexchange/25387-write-cell-array-to-text-file?s_tid=gn_loc_drop
inputname = 'MyFile.TXT';
outputname = 'MyOutput.TXT';
rawinventory = dataset('File', inputname', 'Delimiter', ',',
'ReadVarNames', true);
rawinventory(1,1); %The Command Window shows the first entry and the
%header name without the double quotes.
temp_raw = dataset2cell(rawinventory(:,:));
for y = 1:size(temp_raw,2);
temp_raw(1,y) = strcat('"',temp_raw(1,y),'"');
end %This for loop replaces the double quotes
% Perform some data Manipulation here
%........
dlmcell(outputname,temp_raw,',');
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'
Dear All (with many thanks in advance),
The following script has trouble reading (and therefore writing) the %s character in the file 'master.py'.
I get that matlab thinks the %s is an escape character, so perhaps an option is to modify the terminator, but I have found this difficult.
(EDIT: Forgot to mention the file master.py is not in my control, so I can't modify the file to %%s for example).
%matlab script
%===============
fileID = fopen('script.py','w');
yMax=5;
fprintf(fileID,'yOverallDim = %d\n', -1*yMax);
%READ IN "master.py" for rest of script
fileID2 = fopen('master.py','r');
currentLine = fgets(fileID2);
while ischar(currentLine)
fprintf(fileID,currentLine);
currentLine = fgets(fileID2);
end
fclose(fileID);
fclose(fileID2);
The file 'master.py' looks like this (and the problem is on line 6 'setName ="Set-%s"%(i+1)':
i=0
for yPos in range (0,yOverallDim,yVoxelSize):
yCoordinate=yPos+(yVoxelSize/2) #
for xPos in range (0,xOverallDim,xVoxelSize):
xCoordinate=xPos+(xVoxelSize/2)
setName ="Set-%s"%(i+1)
p = mdb.models['Model-1'].parts['Part-1']
# p = mdb.models['Model-1'].parts['Part-2']
c = p.cells
cells = c.findAt(((xCoordinate, yCoordinate, 10.0), ))
region = p.Set(cells=cells, name=setName)
p.SectionAssignment(region=region, sectionName='Section-1', offset=0.0, offsetType=MIDDLE_SURFACE, offsetField='', thicknessAssignment=FROM_SECTION)
i+=1
In the documentation of fprintf you'll find this:
fprintf(fileID,formatSpec,A1,...,An) applies the formatSpec to all elements of arrays A1,...An in column order, and writes the data to a text file.
So in your function fprintf uses currentLine as format specification, resulting in an unexpected output for line 6. Correct application of fprintf by providing a formatSpec, fixes this issue and doesn't require any replace operations:
fprintf(fileID, '%s', currentLine);
Your script has no trouble reading the % characters correctly. The "problem" is with fprintf(). This function correctly interpretes the percent signs in the string as formatting characters. Therefore, I think you have to manually escape every single % character in your currentLine string:
currentLine = strrep(currentLine, '%', '%%');
At least, it worked when I checked it on your example data.
Thanks applesoup for identifying my fundamental oversight - the problem is in the fprintf - not in the file read
Thanks serial for enhancing the fprintf
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);
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.
how I can read the following files using the for loop: (can the loop ignore the characters in filenames?)
abc-1.TXT
cde-2.TXT
ser-3.TXT
wsz-4.TXT
aqz-5.TXT
iop-6.TXT
What do I have to add at the beginning of this loop ??
for i = 1:1:6
nom_fichier = strcat(['MyFile\.......' num2str(i) '.TXT']);
You can avoid constructing the filenames by using the DIR command. For instance:
myfiles = dir('*.txt');
for i = 1:length(myfiles)
nom_fichier = myfiles(i).name;
...do processing here...
end
First of all, why would you use strcat here? This is, by itself, a SINGLE string. All concatenation has already been done by the brackets [].
['MyFile\.......' num2str(i) '.TXT']
Next, I'm not certain what is your question here. Is it how to load in the data? If the files are simply delimited numbers, with the same number of them on each line, then load will suffice to load them in, or perhaps you may need textread.
My guess is you do not know how to build the main part of of the file name. You might do it this way:
Names = {'abc' 'cde 'ser' 'wsz' 'aqz' 'iop'};
for i = 1:6
fn = ['MyFile',filesep,Names{i},'-',num2str(i),'.TXT'];
data = load(fn);
% do other stuff ...
end
If you don't want to create a variable with the names by typing them in, then use dir, perhaps like this to create a list of text file names:
Names = dir('MyFile\*.TXT');