a replacement function for dlmread in javascript

In JavaScript, we can read data from a file using the FileReader Web API. We can read the contents of the file into a string or an array, and then perform the replacement operation.

Here's an example code that reads a data file, splits it into an array of arrays, and replaces all occurrences of a string with another string:

index.tsx
function replaceData(filepath, searchStr, replaceStr, delimiter) {
  const fileReader = new FileReader();
  
  fileReader.onload = function(event) {
    const contents = event.target.result;
    const lines = contents.split('\n');
    const data = [];
    
    for (let i = 0; i < lines.length; i++) {
      let line = lines[i].trim();
      if (line !== '') {
        data.push(line.split(delimiter));
      }
    }
    
    for (let i = 0; i < data.length; i++) {
      for (let j = 0; j < data[i].length; j++) {
        data[i][j] = data[i][j].replace(searchStr, replaceStr);
      }
    }
    
    console.log(data);
  };
  
  fileReader.readAsText(filepath);
}
666 chars
27 lines

In this code, filepath is the path to the data file. searchStr is the string to search for, replaceStr is the string to replace it with, and delimiter is the character that separates each value in the data file. The code reads the contents of the file, splits it into an array of arrays, and replaces all occurrences of searchStr with replaceStr. Finally, it logs the updated data to the console.

Note that this implementation assumes that the data file is a CSV file. If the file is in a different format, you may need to modify the code to split the lines and the fields differently.