Firefox Tomorrow

javascript instance method

DataView.prototype.getFloat64()

View on MDN ↗

The getFloat64() method of DataView instances reads 8 bytes starting at the specified byte offset of this DataView and interprets them as a 64-bit floating point number. There is no alignment constraint; multi-byte values may be fetched from any offset within bounds.

Interactive exampleOpen the canonical MDN source to run this embedded demo.
// Create an ArrayBuffer with a size in bytes
const buffer = new ArrayBuffer(16);

const view = new DataView(buffer);
view.setFloat64(1, Math.PI);

console.log(view.getFloat64(1));
// Expected output: 3.141592653589793

Syntax

getFloat64(byteOffset)
getFloat64(byteOffset, littleEndian)

Parameters

  • byteOffset
    • : The offset, in bytes, from the start of the view to read the data from.
  • littleEndian Optional
    • : Indicates whether the data is stored in little- or big-endian format. If false or undefined, a big-endian value is read.

Return value

Any number value.

Exceptions

  • RangeError
    • : Thrown if the byteOffset is set such that it would read beyond the end of the view.

Examples

Using getFloat64()

const { buffer } = new Uint8Array([0, 1, 2, 3, 4, 5, 6, 7, 8, 9]);
const dataview = new DataView(buffer);
console.log(dataview.getFloat64(1)); // 8.20788039913184e-304

Specifications

SpecificationsStandards references are available on the canonical MDN page.

Browser compatibility

Browser compatibilityCompatibility data is available on the canonical MDN page.

See also