Introduction
This tutorial gives a complete overview as to how to write an Excel file from Matlab. Lot of times, we come across situations, where we need to save the data or read the data generated from the experimental simulation to an Excel file.
Steps
Step 1: The first step is to create a COM server which runs the Excel Application.
Excel = actxserver('Excel.Application');
This assumes that the Excel Application is installed in your system. If Excel is not installed, this statement will give an error. You can put the above statement between a try-catch block:
try
Excel = actxserver('Excel.Application');
catch
Excel = [];
end
Step 2 : In this step, we will check the version of Excel.
ExcelVersion = str2num(Excel.Version);
If the Microsoft Excel Version installed in your system is 2007, 2010 or above, you would get ExcelVersion would be 12 or above. In such a case, you can handle all the Excel workbook files with extensions *.xls, *.xlsx and *.xlsm. If the version is less than 12, only *.xls file would be supported.
Step 3 : In this step, we will open an Excel file “ResultFile.xls” in the current directory.
ResultFile = [pwd '\ResultFile.xls'];
Workbook = invoke(Excel.Workbooks,'Open', ResultFile);
Step 4: By default, the visibility of the Excel file is set to
FALSE. You can make the Excel file visible using the command:
set(Excel, 'Visible', 1);
Step 5: In this step, let us say, we will add some data in the sheet titled “ExperimentSheet” and take the average of the data.
Let us assume, we are taking the experimental results from 10 different Experiments and we need to populate the results in Column A and Column B as shown in the figure. Finally, we need to take the Average of the Experimental Results using the Excel formula:
=AVERAGE(B2:B11)
The first step is to open the Excel Workbook and activate the 'ExperimentSheet' Sheet. The following code tries to open the 'ExperimentSheet
'
in ResultFile.xls. If the sheet is not found, it adds the Excel sheet and renames it to 'ExperimentSheet
'.
resultsheet = 'ExperimentSheet'
try
sheet = get(Excel.Worksheets,'Item', resultsheet);
invoke(sheet, 'Activate');
catch
% If the Excel Sheet ‘ExperimentSheet’ is not found, Add an
% Excel Sheet, and rename the new sheet
% to ‘ExperimentSheet’
ExcelWorkbook = Excel.workbooks.Add;
set(ExcelWorkbook, 'Name', resultsheet);
end
Add the Header:
In order to write to an Excel File, we are using xlswrite() function. It has a number of advantages
over the xlswrite
function in Matlab. The xlswrite1
function can be downloaded from
here. As seen from the Excel sheet, we need to first add
two headers, “Experiment and Result” in A1 and B1, respectively.
%% Add the Header
Location = 'A1:B1';
[status, message] = xlswrite1(ResultFile,{'Experiment','Result'}, resultsheet, Location);
if status == 0,
errordlg(message.message);
end
In order to make the header bold, we need to select the header:
% Make the header bold
HeaderRange = get(Excel.Activesheet, 'Range', Location);
HeaderRange.Select;
Excel.Selection.Font.Bold = true;
In this step, we need to add the iteration number in the first column:
iter = (1:10)';
Location = 'A2:A11';
[status, message] = xlswrite1(ResultFile num2cell(iter), resultsheet,
Location);
if status == 0,
errordlg(message.message);
end
Similarly, we need to add the Experimental Results to Column B. Let us say, the experimental result is saved in the array ‘ExpResults
’. For
example, we can add the experimental results in the second column as,
ExpResults = [12.34 12.56 12.74 11.66 13.34 12.56 13.56 12.45 12.01 12.98];
Location = 'B2:B11';
[status, message] = xlswrite1(ResultFile num2cell(ExpResults’), resultsheet, Location);
if status == 0,
errordlg(message.message);
end
Computing the Average
We need to add the row AVERAGE on 14th Row.
Location = 'A14:A14';
[status, message] = xlswrite1(ResultFile,{'AVERAGE'}, resultsheet,
Location);
if status == 0,
errordlg(message.message);
end
Entering the Average Formula
Location = 'B14:B14';
Avg_formula = {['=AVERAGE(' xlcolumn(2) '2:' xlcolumn(2) int2str(11) ')']};
[status, message] = xlswrite1(ResultFile, Avg_formula, resultsheet, Location);
if status == 0,
errordlg(message.message);
end
where xlcolumn()
function converts between column name and number for Excel representation. The
xlcolumn()
module can be downloaded from
here.
function loc = xlcolumn(column)
if isnumeric(column)
if column>256
error('Excel is limited to 256 columns! Enter an integer number <256');
end
letters = {'A','B','C','D','E','F','G','H','I','J','K','L','M','N','O','P','Q','R','S','T','U','V','W','X','Y','Z'};
count = 0;
if column-26<=0
loc = char(letters(column));
else
while column-26>0
count = count + 1;
column = column - 26;
end
loc = [char(letters(count)) char(letters(column))];
end
else
letters = ['A','B','C','D','E','F','G','H','I','J','K','L','M','N','O','P','Q','R','S','T','U','V','W','X','Y','Z'];
if size(column,2)==1
loc =findstr(column,letters);
elseif size(column,2)==2
loc1 =findstr(column(1),letters);
loc2 =findstr(column(2),letters);
loc = (26 + 26*loc1)-(26-loc2);
end
end
The last step is to save the Excel file and close the Excel application:
%Save and Close the Excel File
invoke(Workbook,'Save');
invoke(Excel,'Quit');
delete(Excel);
Download: The complete Matlab source can be downloaded below: Download ComputeAverage.zip.