ndarray-gradient

Computes the gradient of an ndarray using a 2-point central finite difference template.

Example

var pack = require('ndarray-pack')
var pool = require('ndarray-scratch')
var grad = require('ndarray-gradient')
var show = require('ndarray-show')

var X = pack([[0, 0, 0],
              [0, 1, 0],
              [0, 0, 0]])

//Compute gradient of X
var dX = grad(pool.zero([3,3,2]), X)

console.log('grad(X) = \n', show(dX))

Output:

grad(X) =
   0.000    0.000    0.000
  -0.500    0.000    0.500
   0.000    0.000    0.000

   0.000   -0.500    0.000
   0.000    0.000    0.000
   0.000    0.500    0.000

Install

npm install ndarray-gradient

API

require('ndarray-gradient')(dst, src[, bc])

Computes the gradient of src storing the result into dst.

• dst is an array of gradient values. The shape of dst must be the shape of src with one additional dimension for the components of the gradient

• src is the array to differentiate

• bc is an array of boundary conditions. The boundary conditions are encoded as string values and must be one of the following values:

  • 'clamp' (Default) clamp boundary edges to boundary
  • 'mirror' mirror values across the boundary
  • 'wrap' wrap values across boundary

Returns dst

Credits

(c) 2014 Mikola Lysenko. MIT License