How to Read an Excel File in Matlab
In this tutorial, you lot will acquire how to read or write data in a spreadsheet file of excel. You can also create a spreadsheet file using LabView every bit y'all will see presently in this tutorial. At the start you are provided with an introduction to spreadsheet files why they are used and what is at that place use in LabView. Later that a VI is designed which create a spreadsheet file write data to information technology and at the end read data from the aforementioned spreadsheet. At the terminate of the tutorial you lot are provided with an exercise to do it by yourself, and in the adjacent tutorials I volition assume that you lot have done those exercises and I volition not explain the concept regarding them.
read and write data to excel files in labview
Data tin be stored in organized cells, such as in rows and columns using a spreadsheet file. Certain blazon of data tin can be stored in each cell of the spreadsheet such every bit numeric, text data, strings or dates etc. Spreadsheet files can also be equanimous of cells which use formulas referring to other cells. A simple spreadsheet file extension is .xlsx, .ods, .numbers and .csv.
Text files also have subset specified equally text-based spreadsheet files. Formatting a string data as a spreadsheet string is a must when you want to write data to a spreadsheet file, which included inserting delimiters in a string such as tabs and commas.
In LabView we can design a 6 that can write different information types to a text file or a .csv file in the form of a spreadsheet. Writing data to a spreadsheet requires string type information separated by a delimiter (a parameter provided to the write to spreadsheet bloc). The function takes the value from the function in the form of timestamp data, numeric data and delimiters and writes the data in the form of strings in a spreadsheet file or a text file with data separated by the delimiter specified.
Examples read and write data to excel files in labview
- I will now try to explain the functionality of working with e spreadsheet in LabView using a Half dozen. Create a VI as we have been doing from tutorial i and salvage information technology for future use. Create a nested loop that will render a 2D array of size ten×x and containing random numbers generated between 0 and 1 as shown in the figure beneath,
Figure 1: 2d array loops
- These loops will generate a 2D array at the auto indexing final of the outer loop. Now from the function palette on the block diagram select file I/O then select write delimiter spreadsheet as shown in the effigy below,
Figure two: Writing to spreadsheet placement
- The write delimited spreadsheet block is shown in the figure below,
Figure three: Write to spreadsheet cake
- If you lot want to know the pins description of the write to spreadsheet block simply open up the context help window as we have done in previous tutorial and hover over the block of write to spreadsheet. The pivot clarification of the write to text block is shown in the effigy below,
Figure 4: Pins description of block
- Connect the output of the nested loops we created at the showtime with the pin of the write to spreadsheet block named every bit 2d information in the pivot description help window as shown in the figure below,
Effigy 5: Cake diagram
- On the pin of the write to spreadsheet block named every bit delimiter create a constant to provide the delimiter between the strings. Past default the delimiter is ready to tab (\t) but if you desire to write data to an excel sheet you must provide a delimiter comma (,) considering tab (\t) is not used for excel sheets. Create a constant at the delimiter as shown in the figure beneath,
Figure half-dozen: Delimiter pin
- And place a comma within the constant for to create a .csv file every bit shown in the effigy beneath,
Figure 7: Comma delimiter
- To the pin named every bit file path specify the path of the file you want to write to. Otherwise a dialog box volition appear equally y'all will see shortly request for y'all to create a spreadsheet file. This is the default belongings of write delimited spreadsheet cake. Run the VI and the Six will inquire you lot where to save the spreadsheet you created. Select the folder where you want to save the spreadsheet and write the name of the spreadsheet with the file extension as shown in the figure below,
Figure 8: Creating spreadsheet file
- This volition create a .csv file in the destination folder you lot select, equally shown in the effigy below,
Figure 9: Saved file in the destination
- The saved file will be located in the form of the file you gave the extension of previously. Open up the file and yous will see a 10×10 second array stored in the spreadsheet file with extension .csv every bit shown in the figure below,
Figure 10: Spreadsheet.csv file
- Using the same block you lot can besides write your spreadsheet information to a text ile changing your delimiter. Y'all tin can also write data to a text file with the aforementioned delimiter simply in case of text file tab (\t) delimiter is preferred because it increases the understand ability of the data. Alter the delimiter of the write to spreadsheet block from comma to tab (\t) as sown in the figure below,
Figure xi: Tab delimiter
- Now run the program once again a dialog box will appear, select the destination folder write the name of the file you want to create and this time, salve the file with file extension .txt as shown in the figure below,
Figure 12: Saving to text file
- This will salve the aforementioned data i.due east. randomly generated second array in a text file with the delimiter as a tab (\t) space betwixt 2 entries. The file will be saved in the binder you lot designated it to be saved as shown in the figure below,
Figure thirteen: Saved text file
- Opening this file will show yous the 2nd randomly generated assortment of size 10×x and delimiter as a tab space as shown in the figure beneath,
Figure xiv: Saved text file
read information from excel spread sheets in labview
- Nosotros tin can too read data from a spreadsheet file we but created. From the function palette on the block diagram window select File I/O and then select Read delimited spreadsheet as shown in the effigy below,
Figure xv: Read from spreadsheet placement
- The cake of read delimited spreadsheet is shown in the figure below,
Effigy xvi: Read from spreadsheet block
- If you desire to see the pins description of the read block, again use the context assistance window as you have done in case of seeing write block pins description. Open the assistance window and then hover over the read delimited spreadsheet cake equally shown in the figure below,
Figure 17: Pins clarification
- If yous want to read all the rows from yous spreadsheet file create an indicator at the all rows pin and if you are interested in reading just i row create an indicator at showtime row pin. Also create a constant at the file path equally shown in the figure below. If yous get out this pin at default and then after running the VI the program will requite you a dialog box and ask you to select the spreadsheet file whose information you want to read.
Effigy eighteen: Reading data block diagram
- On the front panel browse the path of the file y'all want to read data from.
Figure 19: Browsing file path
- If yous desire to read data from the .csv file than select comma every bit a delimiter of the read delimited spreadsheet cake as shown in the effigy below,
Effigy twenty: Reading from excel file
- When you lot run the Six the output will display the information of the spreadsheet file as shown in the figure beneath,
Figure 21: Csv file output
- By default the delimiter of the read block is also set to tab (\t). For reading data from the text file you created previously prepare the delimiter to tab(\t) or else leave it empty, as shown in the figure below,
Effigy 22: Reading from text file block diagram
- When you run the Half dozen past changing the path in the file path cake to .txt file the output of the all rows indicator will display the data of the text file yous created previously equally shown in the effigy beneath,
Figure 23: Output of text file
Exercise:
- Create and open a file using open/create/replace block, write data in information technology using write delimited spreadsheet block, read information from information technology using read delimited spreadsheet file block and so close it using shut file block in a same VI
(Hint: Utilise the context help window to see the pivot names of the blocks you haven't used already)
<< Previous tutorial Side by side tutorial>>
Source: https://microcontrollerslab.com/read-write-data-excel-files-labview/
Belum ada Komentar untuk "How to Read an Excel File in Matlab"
Posting Komentar