I try to save a map as a *.mat file which is quite big. (somewhere around 4 or 5gigs. I cannot be sure because I could never save the file...)
the map is generated by:
[amap, ~] = load_audio(config);
and saved later on by
save('audioMap', 'amap');
Now the generated file is only 218 bytes but no errors occur. Trying to read the contents of the file with whos('-file', 'audioMap.mat') results in the following error:
Warning: Unable to read some of the variables due to unknown MAT-file error.
every record of the map is a cell with 6 values. Now querying the size of the map in the Matlab workspace results in the following output:
Name Size Bytes Class Attributes
amap 2279x1 112 containers.Map
Now clearly the size is not correct but I am able to iterate through the map and all data is present. When querying the size of a record it is approximately 2.5MB.
I also tried to save the variable from the workspace with right-click and save-as with the same result.
Anyone got any ideas why Matlab is not able to properly save this map?
You where attempting to write a MAT-File version 7.0 which has a maximum variable size of 2^31 bytes=2GB
When you attempt to write Variables larger than the limit, the expected behaviour would be to receive a warning when saving the variable.
Warning: Variable 'varname' cannot be saved to a MAT-file whose version is older than 7.3. To save this variable, use the -v7.3 switch. Skipping...
For some reason the warning was not raised, but beeing unable to write such large objects is the expected behaviour.
Related
I'm trying to find a possible way to convert PSS/E native .raw files to Pandapower format.
My objective is to take advantage of the network plotting capabilities that are available in Pandapower.
For that, I have to first be able to load my grid data into Pandapower.
For that, I have to somehow bridge the gap between PSSE .raw to Pandapower.
Literature says that a possible way of doing this is by using the 'psse2mpc' function available in Matpower.
I've tried to use it but I get the following error message:
(quote)
>> psse2mpc('RED1523.raw')
Reading file 'RED1523.raw' ............................................. done.
Splitting into individual lines ...error: regexp: the input string is invalid UTF-8
error: called from
psse_read at line 60 column 9
psse2mpc at line 68 column 21
(unquote)
I'was informed that maybe I should save my .raw file (natively generated with a PSSE/E v33 version) into an older .raw format (corresponding to previous PSS/E versions).
I've tried this as well but still have the same error message.
Apart from getting this error which so far impedes to reach my objective, I've been unable to guess the Pandapower "equivalent .raw" structure. Does anybody know how this input structure looks like in Pandapower?
If I would know how Pandapower needs to get the input data, I could even try to code a taylor-made python script that converts my .raw file into whatever is required from Pandapower.
If somebody could help me to get out of this labyrinth I would be most gratefull !!!
Thanks.
Eneko.
You need to check your .raw file to enter the other Inputs of the psse2mpc function. For instance, if I have the case39.raw file and I want to convert it to matpower format like case39mpc.m, then I must enter something like this:
psse2mpc ('case39.raw', 'case39mpc.m', '1', '29')
I have tried:
saveas(keys ,keyname);
save(keys ,keyname ,'-mat');
save(keys ,keyname);
where keys is a 3006x4104 matrix of the class double.
I tried to use some casting so I would save it as txt file
for keyname I tried - ./newdronephotos/1880key.mat
and newdronephotos/1880key.mat.
It's not working.
In particular, when I'm trying saveas(keys ,keyname);
it's starting to do some processes and then print the error message:
Error using saveas (line 88)
Simulink object array must be a vector
Actually, I just succeeded to solve my own problem.
The function save() expect to have a string of the name of the desired variable.
For example:
Instead of -
save(keyname ,keys);
I needed to write-
save(keyname ,'keys');
I have data stored in the .tdms format, gathering the data of many sensors, measured every second, every day. A new tdms file is created every day, and stored in a folder per month. Using the convertTDMS function, I have converted these tdms files to mat files.
As there are some errors in some of the measurements(e.g. negative values which can not physically occur), I have performed some corrections by loading one mat file at a time, do the calculations and then save the data into the original .mat file.
However, when I try to do what I described above in a loop (so: load .mat in folder, do calculations on one mat file (or channel therein), save mat file, repeat until all files in the folder have been done), I end up running into trouble with the limitations of the save function: so far I save all variables (or am unable to save) in the workspace when using the code below.
for k = 1:nFiles
w{k,1} = load(wMAT{k,1});
len = length(w{k,1}.(x).(y).(z));
pos = find(w{k,1}.(x).(y).(z)(1,len).(y)<0); %Wind speed must be >0 m/s
for n = 1:length(pos)
w{k,1}.(x).(y).(z)(1,len).(y)(pos(n)) = mean([w{k,1}.(x).(y).(z)(1,len).(y)(pos(n)+1),...
w{k,1}.(x).(y).(z)(1,len).(y)(pos(n)-1)],2);
end
save( name{k,1});
%save(wMAT{k,1},w{k,1}.(x),w{k,1}.ConvertVer,w{k,1}.ChanNames);
end
A bit of background information: the file names are stored in a cell array wMAT of length nFiles in the folder. Each cell in the cell array wMAT stores the fullfile path to the mat files.
The data of the files is loaded and saved into the cell array w, also of length nFiles.
Each cell in "w" has all the data stored from the tdms to mat conversion, in the format described in the convertTDMS description.
This means: to get at the actual data, I need to go from the
cell in the cell array w{k,1} (my addition)
to the struct array "ConvertedData" (Structure of all of the data objects - part of convertTDMS)
to the struct array below called "Data" (convertTDMS)
to the struct array below called "MeasuredData" (convertTDMS) -> at this level, I can access the channels which store the data.
to finally access/manipulate the values stored, I have to select a channel, e.g. (1,len), and then go via the struct array to the actual values (="Data"). (convertTDMS)
In Matlab format, this looks like "w{1, 1}.ConvertedData.Data.MeasuredData(1, len).Data(1:end)" or "w{1, 1}.ConvertedData.Data.MeasuredData(1, len).Data".
To make typing easier, I took
x = 'ConvertedData';
y = 'Data';
z = 'MeasuredData';
allowing me to write instead:
w{k,1}.(x).(y).(z)(1,len).(y)
using the dot notation.
My goal/question: I want to load the values stored in a .mat file from the original .tdms files in a loop to a cell array (or if I can do better than a cell array: please tell me), do the necessary calculations, and then save each 'corrected' .mat file using the original name.
So far, I have gotten a multitude of errors from trying a variety of solutions, going from "getfieldnames", trying to pass the name of the (dynamically changing) variable(s), etc.
Similar questions which have helped me get in the right direction include Saving matlab files with a name having a variable input, Dynamically Assign Variables in Matlab and http://www.mathworks.com/matlabcentral/answers/4042-load-files-containing-part-of-a-string-in-the-file-name-and-the-load-that-file , yet the result is that I am still no closer than doing manual labour in this case.
Any help would be appreciated.
If I understand your ultimate goal correctly, I think you're pretty much there. I think you're trying to process your .mat files and that the loading of all of the files into a cell array is not a requirement, but just part of your solution? Assuming this is the case, you could just load the data from one file, process it, save it and then repeat. This way you only ever have one file loaded at a time and shouldn't hit any limits.
Edit
You could certainly make a function out of your code and then call that in a loop, passing in the file name to modify. Personally I'd probably do that as I think it's neater solution. If you don't want to do that though, you could just replace w{k,1} with w then each time you load a file w would be overwritten. If you wanted to explicitly clear variables you can use the clear command with a space separated list of variables e.g. clear w len pos, but I don't think that this is necessary.
I need to make a radar plot, I googled it and got this: http://www.mathworks.co.uk/matlabcentral/fileexchange/33134-radar-plot/content/radarPlot.m
but it gives an error I'm not sure how to solve.
The error is Error: File: radarplottest.m Line: 17 Column: 1
Function definitions are not permitted in this context.
Any tips?
Did you copy the function and paste it into a script file you were working on?
If you did something like add your own code at the top of the file (say, to load data), that will give you the error you're seeing. You should have one file, "radarPlot.m", which contains this function, and then "radarplottest.m" could be something like a script containing data loading/pre-processing and then calling the radarPlot function on the appropriate data.
All you need in radarplottest.m is something like:
Data = % define some random test data or load some existing data
radarPlot(Data); % requires radarPlot.m to be on your path so Matlab can find it
I am reading a dicom file in matlab and modifying some data of it and trying to save it into another file, but while doing so, the private dicom data are either not written at all (when 'WritePrivate' is set to 0) or it's written as a UINT8 array which become incomprehensible and useless. I even tried to copy the data that I get in from the original dicom file to a new structure and write to a new dicom file but even though the private data remains fine in new structure it doesn't remain so in the new dicom file. Is there any way to keep this private data intact while copying in to a new dicom file without changing the matlab dicom dictionary?
I have provided the following code to show what I'm trying to do.
X=dicomread('Bad011_4CH_01.dcm');
metadata = dicominfo('Bad011_4CH_01.dcm');
metadata.PatientName.FamilyName='LastName';
metadata.PatientName.GivenName='FirstName';
birthday=metadata.PatientBirthDate;
year=birthday(1,1:4);
newyear=strcat(year,'0101');
metadata.PatientBirthDate=newyear;
names=fieldnames(metadata);
h=metadata;
dicomwrite(X,'example.dcm',h,'CreateMode','copy');
newh=dicominfo('example.dcm');
Here the data in newh contains none of the private data. If I change the code to the following
dicomwrite(X,'example.dcm',h,'CreateMode','copy','WritePrivate',1);
In this case the private data gets totally changed to some UIN8 array and useless. The ideal solution for my task would be to enable keeping the private data in the newly created dicom file without changing the matlab dicom dictionary.
Have you tried something like:
dicomwrite(uint16(image), fileName, 'ObjectType', 'MR Image Storage', ...
'WritePrivate', true, header);
where "header" is a struct composed of name-value pairs using the same format as header data that you would get from MATLAB's dicominfo function? My general approach to image creation in MATLAB is to avoid using CreateMode 'copy' and instead build my own DICOM header by explicitly copying the attributes that it makes sense to copy and generating my own values for attributes that should have new values.
To write private tags, you would do something like:
header.Private_0045_10xx_Creator = 'MY_PRIVATE_BLOCK';
header.Private_0045_1001 = int32(65535);
If you then write this out using dicomwrite and read it back in using hdr = dicominfo('mynewimg');, you can see that it really did write the value as a 32-bit integer even though, unfortunately, if is always going to read the data in as a vector of uint8 values.
>> hdr.Private_0045_1001
ans =
255
255
0
0
As long as you know what type to expect, you should be able to typecast the data back to the desired type after you've read the header. For example:
>> typecast(hdr.Private_0045_1001, 'int32')
ans =
65535
I know I'm about 8 years late, but have you tried
dicomwrite(..., 'VR', 'explicit')
?
It solves the "reading as uint8" problem for me.
Edit:
Actually, it looks like you need to specify a dicom dictionary with the VR of that tag. If you combine this with 'VR', 'explicit', then the program reading the dicom won't need to dictionary file.