MATLAB: Xlsread create a copy of Excel spreadsheet

xlsread

hi everyone. Xlsread create a copy of a spreadsheet's content into Matlab, or it is just a reading of the file? I have many information into a spreadsheet, and i don't want to do access to the file every time because it could slow the execution.

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if you have excel installed and do not call xlsread in basic mode, xlsread starts Excel (but keep the window invisible), instruct excel to load the file, and then ask excel for a copy of the data in the range you've requested. Finally, it closes the file and quit excel.

It does this every time, so multiple calls to xlsread can be slow. According to the release notes, R2015b supposedly improves the performance of multiple code, but the documentation actually does not say anything about it, so it's unclear how it is improved. A quick reading of the code would indicate it still does the whole start/load/read/unload/quit on every call.

It would be much better to read all the content that you need at once and slice it into variables afterward.

Note that if you don't have excel or call xlsread in basic mode, then matlab attempts to parse the file directly.

Related Solutions

MATLAB: Help concatenating a table row to a specific excel spreadsheet

outputTable=table(VarNameStr,Screen_Grasp_Average,Grasp_Release_Average,difference);
writetable(outputTable,D:\LocationName\DataLocation\Spreadsheet.xlsx);

D:\LocationName\DataLocation\Spreadsheet.xlsx is invalid syntax -- it isn't quoted to be a string and it isn't valid syntax to catenate variables (if the pieces of it other than punctuation) were actually variables. writetable expects the second argument to be an acceptable filename as either a char() vector or a string...you gave it something unrecognizable.

drive='D:';
folder='LocationName\DataLocation';
file='Spreadsheet.xlsx';
writetable(outputTable,fullfile(drive,folder,file));

will solve your filename problem when you properly define the various pieces for your application.

That will NOT solve the problem of appending to the Excel spreadsheet, however; you'll have to use the optional 'Range' argument to set the starting corner of the sheet to write to. BUT you'll have to figure out what the next available row is because there is no 'append' flag for Excel files as there is for sequential text files. This means keeping track of how many records have been written to date and compute the proper range expression based on that.

Depending on how this is going to be used, it may be better to either create the full table first before writing it or reading in the existing data and appending the writing (a lot of overhead) or to just write a sequential text file and then when done read that file and convert it to spreadsheet if think simply must have a spreadsheet.

MATLAB: Can MATLAB generate a window similar to a Microsoft Excel spreadsheet

Although MATLAB does not have a built-in function that can completely mimic Microsoft Excel, you may find the following ideas and resources useful:

First, we have a product called Excel Link which creates an interface between Excel and MATLAB and allows you to integrate MATLAB math and graphics into a Microsoft Excel spreadsheet. Please see the following product URL for more information:

http://www.mathworks.com/products/excellink/

There is also another product, MATLAB Excel Builder, which allows you to convert MATLAB algorithms into Excel Add-ins. Please see the following product URL for more information:

http://www.mathworks.com/products/matlabxl/

Also, please note that we have a built-in function called OPENVAR with limited functionality that lets you open certain classes of arrays for easy viewing and editing. Please type the following at the MATLAB command line for more information:

doc openvar
help openvar

Last, you can search our MATLAB central file exchange for "spreadsheet" or similar words at the following URL:

https://www.mathworks.com/matlabcentral/

This file exchange provides a venue for customers and developers to supply their own user-written code for free. You may find that someone has created a function that will meet your needs.

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MATLAB: Help concatenating a table row to a specific excel spreadsheet

MATLAB: Can MATLAB generate a window similar to a Microsoft Excel spreadsheet

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