small tweaks, handle edge cases

Author: mikolalysenko

fdg.js

@@ -257,7 +257,7 @@ function generateGradient(boundaryConditions) {
     linkArgs.push(generateTemplate(i))
   }
   linkNames.push(code.join(''))
-  
+
   var link = Function.apply(void 0, linkNames)
   var proc = link.apply(void 0, linkArgs)
   TEMPLATE_CACHE[token] = proc
@@ -288,6 +288,10 @@ function gradient(out, inp, bc) {
   if(inp.size === 0) {
     return out
   }
+  if(inp.dimension === 0) {
+    out.set(0)
+    return out
+  }
   var cached = generateGradient(bc)
   return cached(out, inp)
 }

package.json

@@ -15,7 +15,9 @@
     "ndarray": "^1.0.15",
     "ndarray-pack": "^1.1.1",
     "ndarray-scratch": "^1.1.1",
-    "ndarray-show": "^1.1.0"
+    "ndarray-show": "^1.1.0",
+    "tape": "^3.0.0",
+    "ndarray-unpack": "^1.0.0"
   },
   "scripts": {
     "test": "tape test/*.js"

test/test.js

@@ -26,5 +26,9 @@ tape('ndarray-gradient', function(t) {
   t.same(g([1,2], 'clamp'), [[-0.5, -0.5]])
   t.same(g([1,2], 'mirror'), [[0,0]])
 
+  t.same(g([[1,2,3]], 'wrap'), [[[0,0,0]],[[0.5, -1, 0.5]]])
+  t.same(g([[1,2,3]], 'clamp'), [[[0,0,0]],[[-0.5,-1, -0.5]]])
+  t.same(g([[1,2,3]], 'mirror'), [[[0,0,0]],[[0, -1, 0]]])
+
   t.end()
 })