"Variable index exceeds table dimensions" Error

Hello,

I have a MATLAB code that is ued for converting data from a machine to numerical values (I have not developed the code, provided by company). When I'm trying to run the code, it keeps repeating the error message of 'Variable index exceeds table dimensions" even after changing the matrix dimensions in the code. I am attaching the code as well as the machine generated .csv file which is to be converted. Can someone please help remove this error?

Regards,

Ankit

% Controller captures the data for 6 seconds with 500Hz frequency [3000 data points]

clear all; close all; clc;

filename=uigetfile('.csv');
data=readtable(filename);

data(1:2,:)=[]; % get rid of first two rows which contain strings
data_test=data(1:30000,4);      % getting rid of testing info data at the end of table

data_test=strrep(table2array(data_test),',','.');      % convert to cell containing strings and replace comma with dot
data_test=str2double(data_test);    % conversion to double


% we have 10 variables ... each variable is saved at 3000 points
data_real=reshape(data_test,[3000,10]);  % reshape into block

%%
%{
1. energy
2. IstStrom_VM [actual power of prestroke motor]
3. IstDrehmoment_RM [actual torque friction motor]
4. IstStrom_RM [actual power friction motor]
5. s_abs_ist  
6. s_rel_ist
7. Axialkraft_ist [axial force measure from bit]
8. IstGeschwindigkeit_RM [speed friction motor]
9. Stufennummer [step number]
10. Zeit [time]
%}
%% Sort data
% [1.Time 2.StepNumber 3.Energy 4.AxialForce 5.SpeedFrictionMotor 6.TorqueFrictionMotor 
%   7.PowerFrictionMotor 8.PowerPreStrokeMotor 9.AbsDisp 10.RelDisp]

data_sorted=[data_real(:,10) data_real(:,9) data_real(:,1) data_real(:,7) data_real(:,8) data_real(:,3)...
    data_real(:,4)  data_real(:,2) data_real(:,5) data_real(:,6)];



%% save processed file into excel sheet
data_table = array2table(data_sorted,...
    'VariableNames',{'Time_sec','StepNumber','Energy_J','Axial_Force_N','Speed_FM_RPM',...
    'Torque_FM_Nm','Power_FM_', 'Power_PM_','Abs_Disp_mm','Rel_Disp_mm'});
filename=erase(filename,'.csv');

%   writetable(data_table,sprintf('Proc_%s.xlsx',filename));

%% Plotting
idx=max(find(data_sorted(:,2)==4)); % draw till step 4

%figure('units','normalized','outerposition',[0 0 1 1])
figure
subplot(2,1,1)
plot(data_sorted(1:idx,1),data_sorted(1:idx,6),'LineWidth',1.25)
xlim([data_sorted(1,1) , data_sorted(idx,1)])
xlabel('Time'); ylabel('Torque (Nm)');
%grid on
hold on
plot(data_sorted(1:idx,1),data_sorted(1:idx,2),'r','LineWidth',1.25)
% Draw a line right at the end of Step 3
%line([data_sorted(max(find(data_sorted(:,2)==3)),1),data_sorted(max(find(data_sorted(:,2)==3)),1)],[-5 14],...
%    'LineWidth',1.25,'Color','Black')
% legend('Torque','Step Number')
set(gca,'FontSize',15)
subplot(2,1,2)
plot(data_sorted(1:idx,1),data_sorted(1:idx,5),'LineWidth',1.25)
xlim([data_sorted(1,1) , data_sorted(idx,1)])
xlabel('Time'); ylabel('Speed Friction Motor (RPM)'); ylim([0 9000])
%grid on
set(gca,'FontSize',15)


figure
plot(data_sorted(1:idx,1),data_sorted(1:idx,6),'LineWidth',1.25)
xlim([data_sorted(1,1) , data_sorted(idx,1)])
xlabel('Time'); ylabel('Torque (Nm)'); ylim([-15,15])
%grid on
hold on
plot(data_sorted(1:idx,1),data_sorted(1:idx,2),'r','LineWidth',1.25)
% Draw a line right at the end of Step 3
%line([data_sorted(max(find(data_sorted(:,2)==3)),1),data_sorted(max(find(data_sorted(:,2)==3)),1)],[-5 14],...
%    'LineWidth',1.25,'Color','Black')
% legend('Torque','Step Number')
set(gca,'FontSize',15)
figure
plot(data_sorted(1:idx,1),data_sorted(1:idx,5),'LineWidth',1.25)
xlim([data_sorted(1,1) , data_sorted(idx,1)])
xlabel('Time'); ylabel('Speed Friction Motor (RPM)'); ylim([0 9000])
%grid on
set(gca,'FontSize',15)


time_Step2=data_sorted(max(find(data_sorted(:,2)==2)),1)-data_sorted(min(find(data_sorted(:,2)==2)),1);
time_Step3=data_sorted(max(find(data_sorted(:,2)==3)),1)-data_sorted(min(find(data_sorted(:,2)==3)),1);

fprintf('Time Duration of Step 2 is %f\n',time_Step2)
fprintf('Time Duration of Step 3 is %f\n',time_Step3)

[Kevin Chng]

KIndly advise which line cause error.

[madhan ravi]

you forgot to upload the csv file

[ankit varma]

@ Kevin- I am getting the error for line 9.

@madhan- I did upload the csv file. But I'll upload it again.

[Jan]

Which line is "line 9"? Prefer to post the complete error message.

[ankit varma]

@ All- The problem is not with the code but with the version of MATLAB I have been using. The code is running fine when R2017a version is used. Appreciate your help!

Answer 1

[Jan]

If the failing line is:

data_test=data(1:30000,4);

use the debugger to find the cause. Type this in the command window:

dbstop if error

Now start the code again. When Matlab stops at the error, check the size of the used variable:

size(data)

What do you observe? I guess, that data does not have 4 columns.

[ankit varma]

The code is running fine using R2017a version. Appreciate your help.

Answer 2

[quaim abbas]

I am performing code on thingspeak to compare two body vitals in 1 chart .but when i write the code it give me error saying that variable index exceeds table dimensions giving error in this line"sensorData(sensorData{:,3}>100,:)=[];"

startTime = datetime(2021,4,16,04,06,57);
endTime=  startTime+ days(2);
sensorData = thingSpeakRead(1357008,'Location',1,'dateRange',[startTime endTime],...
    'location',1,'outputformat','timetable');
sensorData(sensorData{:,3}>100,:)=[];
plot (sensorData.Timestamps,sensorData.TemperatureF)
ylabel('^0F');
hold;
yyaxis right
plot(sensorData.Timestamps,sensorData.SoilMoisture);
ylabel('Soil Conductivity');
ylim([700 900]);
hold off;

[quaim abbas]

here is link from where i am trying to get help i took the code from here.

https://www.mathworks.com/help/thingspeak/create-custom-channel-view.html

[Walter Roberson]

There are no samples for that time range on that channel, but your code is not testing isempty(sensorData)

Answer 3

[Roya Kakar]

By running the folowing line of code I get the following error message

X=X(:, I);

Error message: Variable index exceeds table dimensions.

[Walter Roberson]

X=X(:, I);

Suppose X is a table, and suppose you are looping over I values.

The first iteration, when I is 1, that would be

X=X(:,1)

which would replace the table X with a table that had only a single variable -- the first variable in the original X table.

The second iteration, when I is 2, that would be

X=X(:,2)

but remember that you replaced the original table X with a new table that only had one variable, so trying to index variable number 2 from it is not going to work as you discarded all variables after the first variable in the first iteration.

Answer 4

[Roya Kakar]

This is my actual code

X = readtable('lingspam_features.csv');
sm =(table2array(X));
[B, I] = sort(sm, 'desc');
X=X(:, I);
X=X(:, 1:500);

Error message: and this line ( X=X(:, I);) shows this error message: Variable index exceeds table dimensions.

[Walter Roberson]

X = array2table(randi(9,7,5))

X = 7×5 table
    Var1    Var2    Var3    Var4    Var5
    ____    ____    ____    ____    ____

     7       3       3       2       7  
     9       6       3       7       2  
     4       5       8       1       4  
     5       7       5       1       3  
     8       8       8       2       4  
     9       5       9       1       1  
     1       5       4       6       7  

sm = table2array(X)

sm = 7×5

7 3 3 2 7 9 6 3 7 2 4 5 8 1 4 5 7 5 1 3 8 8 8 2 4 9 5 9 1 1 1 5 4 6 7

[B, I] = sort(sm, 'desc')

B = 7×5

9 8 9 7 7 9 7 8 6 7 8 6 8 2 4 7 5 5 2 4 5 5 4 1 3 4 5 3 1 2 1 3 3 1 1

I = 7×5

2 5 6 2 1 6 4 3 7 7 5 2 5 1 3 1 3 4 5 5 4 6 7 3 4 3 7 1 4 2 7 1 2 6 6

X(:,I)

Variable index exceeds table dimensions.

When you ask to sort() and you do not provide a dimension number, the sort is along the first non-scalar dimension. If you array has more rows than it has columns, then the resulting indices in I will be between 1 and the number of rows . But you then use the indices as column numbers .

[Walter Roberson]

X = array2table(randi(9,5,7))

X = 5×7 table
    Var1    Var2    Var3    Var4    Var5    Var6    Var7
    ____    ____    ____    ____    ____    ____    ____

     1       6       4       3       6       5       3  
     8       7       3       7       5       3       6  
     7       5       9       6       2       8       7  
     8       7       2       1       4       5       4  
     9       7       4       4       5       4       7  

sm = table2array(X)

sm = 5×7

1 6 4 3 6 5 3 8 7 3 7 5 3 6 7 5 9 6 2 8 7 8 7 2 1 4 5 4 9 7 4 4 5 4 7

[B, I] = sort(sm, 'desc')

B = 5×7

9 7 9 7 6 8 7 8 7 4 6 5 5 7 8 7 4 4 5 5 6 7 6 3 3 4 4 4 1 5 2 1 2 3 3

I = 5×7

5 2 3 2 1 3 3 2 4 1 3 2 1 5 4 5 5 5 5 4 2 3 1 2 1 4 5 4 1 3 4 4 3 2 1

X(:,I)

ans = 5×35 table
    Var5    Var2    Var4    Var3    Var1    Var2_1    Var4_1    Var5_1    Var1_1    Var3_1    Var3_2    Var1_2    Var5_2    Var2_2    Var4_2    Var2_3    Var3_3    Var5_3    Var1_3    Var4_3    Var1_4    Var2_4    Var5_4    Var4_4    Var3_4    Var3_5    Var1_5    Var4_5    Var5_5    Var2_5    Var3_6    Var5_6    Var2_6    Var4_6    Var1_6
    ____    ____    ____    ____    ____    ______    ______    ______    ______    ______    ______    ______    ______    ______    ______    ______    ______    ______    ______    ______    ______    ______    ______    ______    ______    ______    ______    ______    ______    ______    ______    ______    ______    ______    ______

     6       6       3       4       1        6         3         6         1         4         4         1         6         6         3         6         4         6         1         3         1         6         6         3         4         4         1         3         6         6         4         6         6         3         1   
     5       7       7       3       8        7         7         5         8         3         3         8         5         7         7         7         3         5         8         7         8         7         5         7         3         3         8         7         5         7         3         5         7         7         8   
     2       5       6       9       7        5         6         2         7         9         9         7         2         5         6         5         9         2         7         6         7         5         2         6         9         9         7         6         2         5         9         2         5         6         7   
     4       7       1       2       8        7         1         4         8         2         2         8         4         7         1         7         2         4         8         1         8         7         4         1         2         2         8         1         4         7         2         4         7         1         8   
     5       7       4       4       9        7         4         5         9         4         4         9         5         7         4         7         4         5         9         4         9         7         5         4         4         4         9         4         5         7         4         5         7         4         9   

This shows that when the number of rows is less than the number of columns that the indices happen to fall within range of the number of columns, so the indexing succeeds. But are you sure that you want that output, with columns repeated as many times as there are rows ??

I would suggest to you that you do not want to sort() the entire array sm and instead want to sort one single row out of it.

[Roya Kakar]

Thank you so much for your detailed answer. I will take your comments into consideration

Answer 5

[Eirik]

I          = readtable('LindesnesSolenergi.csv','Delimiter',';', 'PreserveVariableNames',1); % Importere alle kolonner fra CSV-fil
I          = table2array(I(1:8760,2))./1000;

Error using ()

Variable index exceeds table dimensions.

Error in Lindesnes (line 2)

I = table2array(I(1:8760,2))./1000;

[Walter Roberson]

Your file LindesnesSolenergi.csv does not have at least 8760 rows after readtable() removed what it thought were headers.

We do not have that file to test with so we do not know the actual size of the file.