Reading Matrix from File in Java - Can Someone Help?

[russel.arnold]

hi want to read the rows of a matrix from a file which are written in the following way :

(2:1,3), (4:3,1), (2:1,8)

i am working in java, i am not able to figure out how to do this using bufferedreader :(

can someone help?

Thanks

 

[uart]

What is the exact meaning of the syntax (2:1,3) etc?

 

[russel.arnold]

(2:1,3) represents 2,1 and 3 elements of a row. ":" and "," are just the delimiters, my task is to separate the integers from these delimiters

 

[uart]

Ok got it. The row element delimiter can be either "," or ':". They are equivalent and they have no other special meaning.

Just to confirm then, in your example you're inputting a 3x3 matrix like the MATLAB equiv of [2,3,1; 4,3,1; 2,1,8]

2 3 1
4 3 1
2 1 8

I'm no expert on java, but if you can't find any easier method then you could always use "bufferedreader.readln()" to read the entire line as a string and then just go through it character by character. Parsing from first principles as it were.

 

[LudusRex]

for reaching out for help with your Java program. Reading data from a file can be a bit tricky, but with the right tools and techniques, it can be done easily. Here are some steps you can follow to read a matrix from a file in Java using a BufferedReader:

1. Create a BufferedReader object: The first step is to create a BufferedReader object to read the file. To do this, you will need to import the java.io package and use the FileReader and BufferedReader classes.

2. Open the file: Next, you will need to open the file that contains the matrix data. You can do this by using the FileReader class and passing the name of the file as a parameter.

3. Read the data: Once the file is open, you can use the BufferedReader object to read the data from the file. You can use the readLine() method to read one line at a time.

4. Split the data: Since the matrix data in the file is written in a specific format, you will need to split each line of data into individual elements. You can use the split() method and specify the delimiter as a comma to separate the elements.

5. Convert the data to a matrix: After splitting the data, you can convert it into a matrix by creating a two-dimensional array and adding the elements to it.

6. Close the file: Once you have finished reading the data, don't forget to close the file using the close() method to free up system resources.

I hope this helps you in reading the matrix data from the file in Java. If you have any further questions, please don't hesitate to ask. Good luck with your program!