Exporting Data

CSV

Frame.toCSV() serialises all scalar channels (stride = 1) to a comma-separated string with a header row.

// All scalar channels
const csv = frame.toCSV();

// Specific channels only
const csv2 = frame.toCSV({ channels: ['DEPTH', 'GR', 'CALI', 'RHOB', 'NPHI'] });

// Custom null representation
const csv3 = frame.toCSV({ nullStr: '-9999.25' });

The output format is:

DEPTH,GR,CALI
1500.0000,45.23,8.50
1500.1000,47.11,8.52
...

Saving to disk (Node.js):

import { writeFileSync } from 'fs';
writeFileSync('well.csv', frame.toCSV());

LAS 2.0

Frame.toLAS() serialises scalar channels to a LAS Version 2.0 string. The ~WELL section is populated from the logical file’s origin.

const las = frame.toLAS();

// Specific channels, custom null
const las2 = frame.toLAS({
  channels:  ['DEPTH', 'GR', 'CALI', 'RHOB', 'NPHI', 'ILD'],
  nullValue: -9999.25,
});

The generated LAS includes:

~VERSION — LAS 2.0, WRAP NO
~WELL — well name, field, company, start/stop depth, step, null, date
~CURVE — channel names and units
~A — numeric data block

Saving to disk (Node.js):

import { writeFileSync } from 'fs';
writeFileSync('well.las', frame.toLAS({ channels: ['DEPTH', 'GR'] }));

Download in the browser

function download(filename, text) {
  const a = document.createElement('a');
  a.href = URL.createObjectURL(new Blob([text], { type: 'text/plain' }));
  a.download = filename;
  a.click();
}

download('well.csv', frame.toCSV());
download('well.las', frame.toLAS());

Working with raw decoded data

For workflows that require more control (e.g. exporting to JSON, feeding a plotting library, or writing other formats), use Frame.decode() directly:

const result = frame.decode();

// Build a plain-object array (one object per depth sample)
const scalarChs = result.channels.filter(c => result.strides[c.name] === 1);
const rows = [];
for (let i = 0; i < result.frameCount; i++) {
  const row = {};
  for (const ch of scalarChs) {
    row[ch.name] = result.data[ch.name][i];
  }
  rows.push(row);
}

console.log(JSON.stringify(rows[0]));
// { DEPTH: 1500, GR: 45.23, CALI: 8.5, ... }