I am trying to load an xls file in MATLAB. The xls file contains numerical values. I have successfully loaded and plotted the file but if I change the dimensions of the file (i.e. number of rows and number of columns) there is an error:
Numeric = xlsread('Test_results_new')
??? No appropriate method or public field UsedRange for class Interface.Microsoft_Excel_12.0_Object_Library._Chart.
Please note that when I make a change in the xls file I also make changes in the MATLAB code for number of rows and columns.
Can someone help me?
I had the same problem recently after months of it continuously working, I found out it was because I had made a plot in the excel file, so (i think) when xlsread was called it was looking at the first sheet (the plot instead of the table) and obviously could not read it. You can specify which sheet to look at with xlsread, just type help xlsread and it will explain how
Related
Unfortunately I am not too tech proficient and only have a basic MATLAB/programming background...
I have several csv data files in a folder, and would like to make a histogram plot of all of them simultaneously in order to compare them. I am not sure how to go about doing this. Some digging online gave a script:
d=dir('*.csv'); % return the list of csv files
for i=1:length(d)
m{i}=csvread(d(i).name); % put into cell array
end
The problem is I cannot now simply write histogram(m(i)) command, because m(i) is a cell type not a csv file type (I'm not sure I'm using this terminology correctly, but MATLAB definitely isn't accepting the former).
I am not quite sure how to proceed. In fact, I am not sure what exactly is the nature of the elements m(i) and what I can/cannot do with them. The histogram command wants a matrix input, so presumably I would need a 'vector of matrices' and a command which plots each of the vector elements (i.e. matrices) on a separate plot. I would have about 14 altogether, which is quite a lot and would take a long time to load, but I am not sure how to proceed more efficiently.
Generalizing the question:
I will later be writing a script to reduce the noise and smooth out the data in the csv file, and binarise it (the csv files are for noisy images with vague shapes, and I want to distinguish these shapes by setting a cut off for the pixel intensity/value in the csv matrix, such as to create a binary image showing these shapes). Ideally, I would like to apply this to all of the images in my folder at once so I can shift out which images are best for analysis. So my question is, how can I run a script with all of the csv files in my folder so that I can compare them all at once? I presume whatever technique I use for the histogram plots can apply to this too, but I am not sure.
It should probably be better to write a script which:
-makes a histogram plot and/or runs the binarising script for each csv file in the folder
-and puts all of the images into a new, designated folder, so I can sift through these.
I would greatly appreciate pointers on how to do this. As I mentioned, I am quite new to programming and am getting overwhelmed when looking at suggestions, seeing various different commands used to apparently achieve the same thing- reading several files at once.
The function csvread returns natively a matrix. I am not sure but it is possible that if some elements inside the csv file are not numbers, Matlab automatically makes a cell array out of the output. Since I don't know the structure of your csv-files I will recommend you trying out some similar functions(readtable, xlsread):
M = readtable(d(i).name) % Reads table like data, most recommended
M = xlsread(d(i).name) % Excel like structures, but works also on similar data
Try them out and let me know if it worked. If not please upload a file sample.
The function csvread(filename)
always return the matrix M that is numerical matrix and will never give the cell as return.
If you have textual data inside the .csv file, it will give you an error for not having the numerical data only. The only reason I can see for using the cell array when reading the files is if the dimensions of individual matrices read from each file are different, for example first .csv file contains data organised as 3xA, and second .csv file contains data organised as 2xB, so you can place them all into a single structure.
However, it is still possible to use histogram on cell array, by extracting the element as an array instead of extracting it as cell element.
If M is a cell matrix, there are two options for extracting the data:
M(i) and M{i}. M(i) will give you the cell element, and cannot be used for histogram, however M{i} returns element in its initial form which is numerical matrix.
TL;DR use histogram(M{i}) instead of histogram(M(i)).
I'm trying to deal with an Excel file which comprises 1 million rows. However, when I open it in MATLAB, only 10,000 rows are displayed.... Could anyone tell me how to import full data using MATLAB?
Type at your MATLAB Command Window:
[~,~,data] = xlsread('X:\path to your file\excel file.xls');
where you should replace the xlsread argument with something that's suitable. The result will be a cell array of mixed numeric (if they could be converted) and strings read from the first sheet in the file. First cell in data corresponds to the upper/left cell in the worksheet.
If you want to specify the sheet, or for more refined function call, read the function's help.
NB
Some of the ways to call the xlsread function are possible or not depending on whether you have Office installed or not.
I have large .bin files (10GB 60GB) that I want to import to MATLAB; each binary file represents the output of two sensors, thus there are too columns of data. Here is a more manageable sized example of my data.
You will notice that there is a .txt version of the data; I need to upload the .bin files directly to MATLAB, I can't use the .txt version because it takes hours to convert with larger files.
The problem I have is that the .bin file has header information that I can't seem to interpret properly, and thus I cannot extract the data in MATLAB every time I try I seem to get gibberish values.
This is all the information I have about the binary header:
Loading Labview Binary Data into Matlab
LabVIEW Data Logger: Binary Header File Format
Any help/advice would be much appreciated I have been trying to solve this problem for days now.
P.S. Someone has already written a function to solve this problem but it does not seem to work with my binary data (could be something to do with the dimensions/size of my data): http://www.mathworks.co.uk/matlabcentral/fileexchange/27195-load-labview-binary-data
Below is the code that I am using to import my data, I believe that that d1 and d2 are the dimensions of my binary data. D2 is probably incorrect for the example file in the dropbox because it has been truncated.
The problem I have is that the code extracts my data and I know it is correct because I can check it with the .txt file (also in the drop box) however there are seaming random bad values between the good data points. These bad values result from the following strings following strings: "NI_ChannelName", "Sensor A", "Sensor B", "NI_UnitDescription", and "Volts" scatted throughout the binary file.
clear all
clc
fname = 'RTL5_57.bin';
fid = fopen(fname,'r','ieee-be');
d1 = fread(fid,4);
trash=fread(fid,2,'double');
d2 = fread(fid,4);
trash=fread(fid,1,'double');
data=fread(fid,'double');
I suppose you will need to change the data-format. See Matlab help.
https://decibel.ni.com/content/docs/DOC-39038
Scope:
1) Write a binary file in matlab and read into labview. 2) Write a binary file in labview and read into matlab.
Background:
IMPORTANT:
You must know (3) things about the binary data in the file before you can read the data:
1) what binary format (precision) was used to store the data
2) the exact number of values in the file to read.
3) Endianness
There is no row or column in binary files. Think of a long row/or a long column that needs to be mapped to a 2D array.
Resources on data in binary format.
http://cse.unl.edu/~sincovec/Matlab/Lesson%2024/Binary/CS211%20Lesson%2024%20-%20Binary%20File%20Input-Output.htm
I have a large text file with 2 columns where the values are separated by commas. I am trying to create a simple program which allows to plot a graph with the data extracted for every 3 rows consecutively until reaching the end of the file.
The first 9 rows of my file can be seen below:
115,1.2
324,3.4
987,1.2
435,-2.3
234,1.4
278,1.3
768,3.4
345,-1.3
126,3.6
I have been reading that with 'Textread' I can write my data into multiple outputs and then I can use 'plot', to plot the previous generated outputs on a graph. I know that I will need some loop whiles to repeat the process and indicate the end of the file, etc. But I am struggling to find the way to do this:-(.
I have only managed plotting a graph for the first 3 rows of my file (see code below), but I need this process to be repeated until the end of the file.
[Codes,Values]=textread('MyData.txt','%3u %f',3,'delimiter',',','emptyvalue',NAN); %//Reads the first three rows of my file and stores the values in 2 variables
figure
plot(Codes,Values) %//plots a graph with the variables obtained before
saveas(gcf,'Graph.pdf') %//Saves the created graph in a pdf format file.
I would be very grateful if somebody could help me.
I have finally found out a way. I paste here the code that allows me plotting a graph every three lines from my text file.
[Codes,Values]=textread('MyData.txt','%3u %f','delimiter',',','emptyvalue',NAN); %//Reads my text file and stores the values in 2 variables
nrows=1;
conta=1;
contb=3;
contc=1;
contd=3;
nfig=1;
while nrows<=size(Codes,1)
if contb<=size(Codes,1)
Codes1=Codes(conta:contb,1);
Values1=Values(contc:contd,1);
figure
plot(Codes1,Values1) %//plots a graph with the selected rows.
saveas(gcf,strcat('Graph', num2str(nfig),'.pdf')) %//Saves the created graph in a pdf format file.
else
Codes1=Codes(conta:contb,1);
Values1=Values(contc:contd,1);
figure
plot(Codes1,Values1) %//plots a graph with the selected rows.
saveas(gcf,strcat('Graph', num2str(nfig),'.pdf'))
end
nrows=nrows+3;
conta=conta+3;
contb=contb+3;
contc=contc+3;
contd=contd+3;
nfig=nfig+1;
end
You mentioned that it is a large text file, but will it an issue to load the whole text file and then simply sample every third row, for example, as follows:
[Codes, Values] = textread('MyData.txt','%3u %f','delimiter',',','emptyvalue',NAN);
rowstokeep = 1:3:length(Values) % every third line
plot(Codes{rowstokeep}, Values{rowstokeep}); % plot just the rows you wanted
I have an excel file to open matlab and put into an array of cells - then take the numbers in the cells and convert a few measurements. how do i do this
I'd suggest looking into the two functions xlsread and xlswrite These both handle input (from an .xls or .xlsx) file to matlab and output from matlab to an excel file, respectively. If you're looking to do something different than that, please elaborate a bit more than what you've posted.