adding in support for offset indices

Author: mikolalysenko

README.md

@@ -53,6 +53,9 @@ To use the library, you pass it an object with the following fields:
  + `"scalar"`: A globally broadcasted scalar argument
  + `"index"`: (Hidden) An array representing the current index of the element being processed. Initially [0,0,...] in the pre block and set to some undefined value in the post block.
  + `"shape"`: (Hidden) An array representing the shape of the arrays being processed
+ + (Hidden) An object containing two properties reprsenting an offset pointer from an array argument.
+ + `offset` An array representing the relative offset of the object
+ + `array` The index of an array parameter
 * `pre`: A function to be executed before starting the loop
 * `body`: (Required) A function that gets applied to each element of the input arrays
 * `post`: Executed when loop completes

package.json

@@ -8,7 +8,7 @@
  },
  "dependencies": {
  "cwise-parser": "~0.0.1",
- "cwise-compiler": "~0.0.0"
+ "cwise-compiler": "~0.1.0"
  },
  "devDependencies": {
  "ndarray": "~1.0.1",

test/offset.js

@@ -0,0 +1,56 @@
+var cwise = require("../cwise.js")
+ , ndarray = require("ndarray")
+ , test = require("tap").test
+
+function DumbStorage(n) {
+ this.data = new Int32Array(n)
+ this.length = n
+}
+DumbStorage.prototype.get = function(i) { return this.data[i] }
+DumbStorage.prototype.set = function(i, v) { return this.data[i]=v }
+
+
+test("offset", function(t) {
+
+ var binary = cwise({
+ args: ["array", "array", {offset:[1], array:1}, "scalar", "shape", "index"],
+ body: function(a,b,c,t,s,idx) {
+ t.equals(a, 0, "idx:"+idx+", shape:"+s)
+ a = c + b + 1000
+ }
+ })
+ 
+ function testBinary1D(P, Q) {
+ console.log(P.shape.toString(), Q.shape.toString())
+ for(var i=0; i<P.shape[0]; ++i) {
+ Q.set(i, i)
+ P.set(i, 0)
+ }
+ Q.set(P.shape[0], P.shape[0])
+ binary(P, Q, t)
+ for(var i=0; i<P.shape[0]; ++i) {
+ t.equals(P.get(i), 2*i+1001)
+ }
+ }
+ 
+ var A = ndarray(new Int32Array(128))
+ var B = ndarray(new Int32Array(129))
+ 
+ testBinary1D(ndarray(new Int32Array(0)), ndarray(new Int32Array(1)))
+ testBinary1D(ndarray(new Int32Array(1)), ndarray(new Int32Array(2)))
+ testBinary1D(A, B)
+ testBinary1D(A.lo(32), B)
+ testBinary1D(A.step(-1), B)
+ testBinary1D(A, B.step(-1))
+ 
+ A = ndarray(new DumbStorage(128))
+ B = ndarray(new DumbStorage(129))
+ testBinary1D(ndarray(new DumbStorage(0)), ndarray(new DumbStorage(1)))
+ testBinary1D(ndarray(new DumbStorage(1)), ndarray(new DumbStorage(2)))
+ testBinary1D(A, B)
+ testBinary1D(A.lo(32), B)
+ testBinary1D(A.step(-1), B)
+ testBinary1D(A, B.step(-1))
+ 
+ t.end()
+})