Writematrix command not working in MATLAB - matlab

sname='Sheet1';
startingColumn='A';
nextRow='1';
filename = 'C:\Users\vvb\Documents\New\ltp.xlsx';
ltp_hist_uper=hist(ltp_uper,10);
ltp_hist_lower=hist(ltp_lower,10);
ltp_full=[ltp_hist_uper ltp_hist_lower]; % contatinate both uper and lower vectors
range=sprintf('%s%d',startingColumn,nextRow);
writematrix(ltp_full,filename,sname,range);
I have download this code for extracting features from and audio file and store those features in matrix in Excel but writematrix command is throwing an error i.e. Invalid parameter name: Sheet1.


The arguments for 'writematrix' function following the initial two are in name-value pair combination. In this case, you should be able to proceed with your requirement by using the following:
writematrix(ltp_full, filename,'Sheet', sname, 'Range',range);

Related

Write Matrix Data to Each Member of Datatype in HDF5 file via MATLAB

This is my first go at trying to create an HDF5 file from scratch using the Low-Level commands via MATLAB.
My issue is that I am having a hard time trying to write data to each specific member in the datatype on my dataset.
First, I create a new HDF5 file, and set the right layer of groups:
new_h5 = H5F.create('new_hdf5_file.h5','H5F_ACC_TRUNC','H5P_DEFAULT','H5P_DEFAULT');
new_h5 = H5G.create(new_h5,'first','H5P_DEFAULT','H5P_DEFAULT','H5P_DEFAULT');
new_h5 = H5G.create(new_h5,'second','H5P_DEFAULT','H5P_DEFAULT','H5P_DEFAULT');
Then, I create my datatype:
datatype = H5T.create('H5T_compound',20);
H5T.insert(datatype,'first_element',0,'H5T_NATIVE_INT');
H5T.insert(datatype,'second_element',4,'H5T_NATIVE_DOUBLE');
H5T.insert(datatype,'third_element',12,'H5T_NATIVE_DOUBLE');
Then, I format that into my dataset:
new_h5 = H5D.create(new_h5,'location',datatype,H5S.create('H5S_SCALAR'),'H5P_DEFAULT');
subset = H5D.get_type(H5D.open(new_h5,'/first/second/location'));
mem_type = H5T.get_member_type(subset,0);
I receive an error with the following command:
H5D.write(mem_type,'H5ML_DEFAULT','H5S_ALL','H5S_ALL','H5P_DEFAULT',data);
Error using hdf5lib2
Unhandled HDF5 class (H5T_NO_CLASS) encountered. It is not possible to write to this attribute or dataset.
So, I try this method instead:
new_h5 = H5D.create(new_h5,'location',datatype,H5S.create_simple(2,dims,dims),'H5P_DEFAULT'); %where dims are the dimensions of all matrices of data structure
H5D.write(mem_type,'H5ML_DEFAULT','H5S_ALL','H5S_ALL','H5P_DEFAULT',data); %where data is a structure
I receive an error with this following command:
H5D.write(mem_type,'H5ML_DEFAULT','H5S_ALL','H5S_ALL','H5P_DEFAULT',data);
Error using hdf5lib2
Attempted to transfer too many values to or from the library buffer.
When looking here for the XML tags for the error messages, it describes the above error as "illegalArrayAccess." Apparently, according to this question, you can only write to 4 members without the buffer throwing an error?
Is this correct? How can I correctly write to each member. I am about to reach my mental limit trying to figure this one out.
EDIT:
References kept here for general information:
HDF5 Compound Datatypes Example
HDF5 Compount Datatypes
H5D.write MATLAB Command

I found out why I cannot write data. I have solved the problem. I had my dimensions set incorrectly (which is code I forgot to include originally). My apologies. I had my dimensions like this:
dims = fliplr(size(data_matrix));
Where dims was a 15x250 matrix. The error was in that the buffer was unable to write a 250x15 matrix for each member, because it only had data for a 250x1 for each member.
The following code will (generically) work for writing data to each member:
new_h5 = H5F.create('new_hdf5_file.h5','H5F_ACC_TRUNC','H5P_DEFAULT','H5P_DEFAULT');
new_h5 = H5G.create(new_h5,'first','H5P_DEFAULT','H5P_DEFAULT','H5P_DEFAULT');
new_h5 = H5G.create(new_h5,'second','H5P_DEFAULT','H5P_DEFAULT','H5P_DEFAULT');
datatype = H5T.create('H5T_compound',20);
H5T.insert(datatype,'first_element',0,'H5T_NATIVE_INT');
H5T.insert(datatype,'second_element',4,'H5T_NATIVE_DOUBLE');
H5T.insert(datatype,'third_element',12,'H5T_NATIVE_DOUBLE');
dims = fliplr(size(data_matrix)); dims = [1 dims(1,2)];
new_h5 = H5D.create(new_h5,'location',datatype,H5S.create_simple(2,dims,dims),'H5P_DEFAULT');
H5D.write(new_h5,'H5ML_DEFAULT','H5S_ALL','H5S_ALL','H5P_DEFAULT',data_structure);
where data_matrix is a 15x250 matrix containing all data, and where data_structure is a sctucture containing 15 fields, each 250x1 in size.

Get Maximum and Minimum value from rrd file generated by Cacti

I have an rrd file in which traffic_in and out stats of interfaces are stored.
What i want is that i want Max and min values in certain time period.
I'm trying this command but it is giving me error ERROR: invalid rpn expression in: v,MAX
rrdtool graph -s 1537466100 -e 1537552237 DEF:v=lhr-spndc-7609_traffic_in_612.rrd:traffic_in:MAX CDEF:vm=v,MAX PRINT:vm:%lf
Can you please help to enter correct command & achieving desired Functionality?

You should be using VDEF for the definition of vm, not CDEF.
A CDEF is for transforming one or more data series created by either a DEF or CDEF into another series, ready for graphing or summarising.
A VDEF is for transforming a single data series into a single value via a consolodation function, such as to get the maximum value of a series over the entire graph. This is different from the function specified in a DEF, which only specifies how to consolodate a higher-granularity series into a lower-granularity series.

How to use saveas() to save a .mat or .txt in specific directory on ubunto

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');

Modify one odeset parameter

I am using ode15s to solve a DAE problem. I give through odeset the Mass Matrix and some more info:
opts=odeset('Mass',M,'MassSingular','yes','MStateDependence','none');
I calculate also Jpattern from a previous run. To feed it to the function, I could write once again
opts=odeset('Mass',M,'MassSingular','yes','MStateDependence','none', 'JPattern',JPat);
Is there a way to modify that single parameter and keep the rest of the structure?
I tried
opts.JPattern = JPat;
But it is not working.

You can probably do something like:
opts = odeset('Mass',M,'MassSingular','yes','MStateDependence','none');
opts = odeset(opts,'JPattern',JPat);
This is using the syntax (see the documentation):
options = odeset(oldopts,'name1',value1,...) alters an existing
options structure oldopts. This sets options equal to the existing
structure oldopts, overwrites any values in oldopts that are
respecified using name/value pairs, and adds any new pairs to the
structure. The modified structure is returned as an output argument.

Save and load fft to .mat file

I have an FFT and I want to save this to .mat file and then read it from that .mat file. I want to use my loaded data for a division. Here is my code
save ('file_fft','a_fft');
b = load ('file_fft');
c = abs (d_fft) ./ abs (b);
In my command window I see that
b = file_fft [4000 * 1 double].
And then I get error message
'Undefined function 'abs' for input arguments of type 'struct''
I tried after deleting abs. I got this error
'Undefined function 'rdivide' for input arguments of type 'struct''
Does anybody have any idea that why it is not working and how i can solve it?

Check the documentation for the load function:
S = load(___) loads data into S, using any of the input arguments in
the previous syntax group.
If filename is a MAT-file, then S is a structure array.
If filename is an ASCII file, then S is a double-precision array
containing data from the file.
So b is a structure and as suggested in the comment, you need to access the data as abs(b.a_fft).

The problem is that load() already creates the file structure that is inside the .mat file. When you assign file_fft with load, it creates a struct.
From the documentation of load():
S = load(_) loads data into S, using any of the input arguments in
the previous syntax group.
If filename is a MAT-file, then S is a structure array.
Edit:
I got sniped :-P
Here's another working example of code:
save ('file_fft','a_fft');
load ('file_fft');
c = abs (d_fft) ./ abs (file_fft);