Node.js Buffer.writeDoubleBE() Method

The Buffer.writeDoubleBE() method is an inbuilt application programming interface of class Buffer within the Buffer module which is used to writes big endian 64-bits double value to an allocated buffer at the specified offset. Syntax:

Buffer.writeDoubleBE( value, offset )

Parameters: This method accept two parameters as mentioned above and described below:

value: This parameter specifies 4 bytes floating point value to be written to the buffer. It should be a valid 64 bits big endian double value. Behavior is undefined when value is anything other than this.
offset: It specifies the number of bytes to skip before write or simply signify the index in the buffer. The value of offset lies 0 <= offset <= Buffer.length - 8. Its default value is 0.

Return Value: This method returns an integer value that is the sum of offset and number of bytes written. Below examples illustrate the use of Buffer.writeDoubleBE() method in Node.js: Example 1:

javascript

// Node.js program to demonstrate the 
// Buffer.writeDoubleBE() method 
     
// Allocating 32 bytes buffer
const buf = Buffer.allocUnsafe(32);

// Writing 64bits or 8 bytes double values
// to the buffer and printing returned
//  value to console
console.log(buf.writeDoubleBE(123.123, 0));
console.log(buf.writeDoubleBE(166.089, 8));
console.log(buf.writeDoubleBE(231.678, 16));
console.log(buf.writeDoubleBE(341.781, 24));
 
// Display the buffer
console.log(buf);

Output:

Example 2:

javascript

// Node.js program to demonstrate the 
// Buffer.writeDoubleBE() method 
     
// Allocating 16 bytes buffer
const buf = Buffer.allocUnsafe(16);

// Printing buffer before writing value
console.log("Before writing into buffer:");
console.log(buf);
 
// Writing 64 bits or 8 bytes double values
// to the buffer and printing returned
// value to console
console.log(buf.writeDoubleBE(219.098, 0));
console.log(buf.writeFloatBE(169.096, 8));
 
// Printing the buffer after writing into buffer
console.log("After writing into buffer:");
console.log(buf);

Output:

Before writing into buffer:

8
12
After writing into buffer:

Note: The above program will compile and run by using the node index.js command. Reference: https://nodejs.org/api/buffer.html#buffer_buf_writedoublebe_value_offset

Node.js Buffer.writeDoubleBE() Method

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