ndarray-stencil

Stencil iterators for ndarrays. This code can be used to implement things like cellular automata or various PDE operations on ndarrays.

Example

var zeros = require("zeros")
 
var points = [[-1, 0], [1, 0], [0,-1], [0, 1]]
 
var diffuse = require("ndarray-stencil")(points, function(a, b, c, d) {
  return 0.25 * (a + b + c + d)
})
 
var x = zeros([5,5])
var y = zeros([5,5])
 
x.set(2,2,1)
 
diffuse(y, x)
 
//Now:
//
// y =[ [ 0, 0,    0,    0,    0 ],
//      [ 0, 0,    0.25, 0,    0 ],
//      [ 0, 0.25, 0,    0.25, 0 ],
//      [ 0, 0,    0.25, 0,    0 ],
//      [ 0, 0,    0,    0,    0 ] ]

Install

npm install ndarray-stencil

require("ndarray-stencil")(points, stencil_func[, options])

Creates a stencil operator for an ndarray.

• points is a list of points that the stencil will be evaluated on
• stencil_func(...) is a function that takes in n arguments, where n is the number points to evaluate the stencil on, and returns the new value of the grid on the given point.
• options is an object containing a list of optional properties:
  • useIndex If this flag is set, add an extra index parameter as the last argument to stencil_func. (Default false)
  • sameOutput if set, then the output is not sliced and instead the result of the stencil operation is applied directly to output

Returns A function that applies the stencil to two arrays. The first argument is the output array, and the second is the input.

Credits

(c) 2013 Mikola Lysenko. MIT License