I am trying to read values from a text file. I want the value after ': '.
Here is a sample of the text file. All lines are formated the same.
There are 34 places before the start of the data.
File Name : IMG_1184.JPG
File Size : 2.1 MB
File Modification Date/Time : 2012:07:14 11:53:18-05:00
File Permissions : rw-rw-rw-
File Type : JPEG
MIME Type : image/jpeg
Exif Byte Order : Big-endian (Motorola, MM)
I tried to use this code:
fileID = fopen('Exif.txt');
Exif1 = textscan(fileID, '%s %s','delimiter', ':');
This worked on most of the data but some data also used ':' so that didn't work.
I tried to use this code:
fileID = fopen('Exif.txt');
Exif1 = textscan(fileID, '%s %s','delimiter', ': ');
This returned a mess. Not sure why. Everything was fragmented.
Can anyone explain how to just get the 35th value to the end of every string and put it into an array?
There is the function strtrim(string) in Matlab which will strip the leading and trailing spaces for you. Try reading the data in a line at the time into the textscan function after using strtrim?
Read the whole line into a variable then get the 35th and subsequent characters like this:
whole_line(35:end)
Related
I would like to save all simulation variables ad fig with the current time.
my solution:
t = datetime('now','Format','dd-MM-yyyy''_T''HHmmss');
t2 = datevec(t);
DateString = datestr(t2);
filename=[DateString,' all_variables_main '];
save(filename )
savefig(filename)
The following error was given in Matlab:
Unable to write file 26-Oct-2019 09:47:15 all_variables_main : Invalid argument.
What have I done wrong?
mat filenames cannot have spaces or colons in them. You can use the following to directly obtain the date and time in a format that is allowed in a filename:
>> fileName = [datestr(now, 'dd-mmm-yyyy_HHMMSS') '_all_variables_main']
fileName =
'26-Oct-2019_103123_all_variables_main'
>> save(fileName)
File name containing : character is not a valid file name.
You can replace the : with "꞉" character.
See: How to get a file in Windows with a colon in the filename?
You can replace all : with ꞉ character (unicode character A789 that looks like colon) that is valid to be used in file name.
filename(filename == ':') = char(hex2dec('A789'));
Make sure to use the right character when loading the file.
Remark: The above solution was tested in Windows 10, and MATLAB R2016a.
I have a text file that consists of line after line of data in an xml-like format like this:
<item type="newpoint1" orient_zx="0.8658983248810842" orient_zy="0.4371062806139187" orient_zz="0.2432245678709263" electrostatic_force_x="0" electrostatic_force_y="0" electrostatic_force_z="0" cust_attr_HMTorque_0="0" cust_attr_HMTorque_1="0" cust_attr_HMTorque_2="0" vel_x="0" vel_y="0" vel_z="0" orient_xx="-0.2638371745169712" orient_xy="-0.01401379799313232" orient_xz="0.9644654264455047" pos_x="0" cust_attr_BondForce_0="0" pos_y="0" cust_attr_BondForce_1="0" pos_z="0.16" angvel_x="0" cust_attr_BondForce_2="0" angvel_y="0" id="1" angvel_z="0" charge="0" scaling_factor="1" cust_attr_BondTorque_0="0" cust_attr_BondTorque_1="0" cust_attr_BondTorque_2="0" cust_attr_Damage_0="0" orient_yx="0.4249823952954215" cust_attr_HMForce_0="0" cust_attr_Damage_1="0" orient_yy="-0.8993006799250595" cust_attr_HMForce_1="0" orient_yz="0.1031903618333235" cust_attr_HMForce_2="0" />
I'm only interested in the values within the " " so I'm trying to read this with textscan. To do this I take the first line and do regex find/replace to swap all number for %f and strings for %s, like this:
expression = '"[-+]?\d*\.?\d*"';
expression2 = '"\w*?"';
newStr = regexprep(firstline,expression,'"%f"');
FormatString = sprintf('%s',regexprep(newStr,expression2,'"%s"'));
The I re-open the file to read the files with string with the following call:
while ~feof(InputFile) % Read all lines in file
data = textscan(InputFile,FormatString,'delimiter','\n');
end
But all i get is an array of empty cells. I can't see what my mistake is - can someone point me in the right direction?
Clarification:
Mathworks provides this following example for textscan to remove literal text, which is what I'm trying to do.
"Remove the literal text 'Level' from each field in the second column of the data from the previous example."
filename = fullfile(matlabroot,'examples','matlab','scan1.dat');
fileID = fopen(filename);
C = textscan(fileID,'%s Level%d %f32 %d8 %u %f %f %s %f');
fclose(fileID);
C{2}
Ok, after looking at this with some fresh eyes today I spotted my problem.
newStr = regexprep(firstline,expression,'"%f"');
FormatString = sprintf('%s',regexprep(newStr,expression2,'%q'));
data = textscan(InputFile,FormatString,'delimiter',' ');
The replacement of the string need to be switched to the %q option which allows a string within double quotes to be read and the delimiter for textscan needed to be reverted to a single space. Code working fine now.
I am attempting to read in multiple file names from a .txt file. Each file names has multiple spaces and ends in different file formats.
When I try this code
M = textread('playlist.m3u', '%s')
I get the results to be the first string in the first row followed by the next string after the space is the next row ect.
One of the file names in the text file is "C:\Users\user\Music\Pink Floyd\Wish You Were Here (Matersound Gold Limited Edition)\03 - Have a Cigar.flac"
'C:\Users\user\Music\Pink'
'Floyd\Wish'
'You'
'Were'
'Here'
'(Matersound'
'Gold'
'Limited'
'Edition)\03'
'-'
'Have'
'a'
'Cigar.flac'
How do I simply read in all the files with each file taking up 1 cell in an cell array?
Use textscan and specify newline \n as the delimiter:
fid = fopen('playlist.m3u');
M = textscan(fid, '%s', 'delimiter', '\n')
I have of bunch of CSV files to read in Matlab. All of files has similar structure, except last field is optional. I.e. some files contain it, others are not.
Also files contain both textual and numeric fields, so csvread is not applicable.
Only alternative I know is textscan. Unfortunately, I can't find specifiers for optional fields.
I am looking at spec:
formatSpec = '%d%f%f%f%f%f%f%f%f%f%f%f%f%f%f%f%f%f%f%f%f%f%f%f%f%f%f%f%f%f%f%f%f%f%f%f%f%f%f%f%f%f%f%f%f%f%f%f%f%f%f%f%f%f%f%f%f%f%f%f%f%f%f%f%f%f%f%f%f%f%f%f%f%f%f%f%f%f%f%f%f%f%f%f%f%f%f%f%f%f%f%f%f%f%s%[^\n\r]';
and wish last %s be optional.
You could try the strsplit function
http://www.mathworks.com/help/matlab/ref/strsplit.html
To read a file line-by-line, you can use the function fgetl. It reads one line, removes newline-characters and returns the line as a string. At the end of the file, a -1 is returned.
You can then use the sscanf to extract the data according to your format spec (including the %s). If your input data doesn't contain any string at the end, then the last field was empty.
fid = fopen('file.txt','r');
while 1
line = fgetl(fid);
if line == -1
break;
end
A = sscanf(line,formatSpec);
...
end
You can then do whatever you need with A.
For example look at the following example:
line = '1 2.5 3.6 abc';
A = sscanf(line,'%d %f %f %s')
A =
1.0000
2.5000
3.6000
97.0000
98.0000
99.0000
The string will be A(4:end). The string was empty if isempty(A(4:end)), that way you can store the data as you like, e.g. in a cell.
Assuming you don't need the optional column, why not ignore the rest of the line by %*s and delimiter set to newline?
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, ...