In Julia, we can read a file using open() function to open the file and then read the contents using one of the various read functions.
Here's an example:
Suppose we have a file called data.txt in the same directory as the Julia code, that contains the following data:
1,John,Doe
2,Jane,Smith
3,Bob,Johnson
We can read this file using the following code:
# Open the file
file = open("data.txt")
# Read the contents of the file
contents = readlines(file)
# Close the file
close(file)
In this example, open() function is used to open the file and the returned file object is assigned to the variable file. readlines() function is used to read all the lines from the file and return them as an array of strings. Finally, close() function is used to close the file.
Now, we can print the contents of the file as follows:
for line in contents
println(line)
end
This will print the following output:
1,John,Doe
2,Jane,Smith
3,Bob,Johnson
Alternatively, we could use the readcsv() function to read a CSV file directly into a matrix of values.
For example, suppose the contents of data.txt are stored in a CSV format, like below:
1,John,Doe
2,Jane,Smith
3,Bob,Johnson
We can read and print the contents of the file using the following code:
# Read data from CSV file
data = readdlm("data.txt", ',')
# Print each row of the data
for row in data
println(row)
end
This will print the following:
1.0 3.0 6.0
2.0 4.0 7.0
3.0 5.0 8.0
Note that readdlm() function is used to read the data from CSV file. It takes the path of the file and the delimiter as its arguments. The delimiter used in this example is ,. Also, the returned matrix contains floating-point numbers. To read strings instead, we can use readdlm("data.txt", ',', String).