fixes an issue where random wasn't random and tests generation

specifically, `imshow` let me see some structure in a “random” matrix.
Turns out changing the seed helped this.

swix/swix.xcodeproj/xcuserdata/scott.xcuserdatad/xcdebugger/Breakpoints_v2.xcbkptlist

@@ -88,11 +88,11 @@
             ignoreCount = "0"
             continueAfterRunningActions = "No"
             filePath = "swix/swix/tests/tests.swift"
-            timestampString = "462756782.87901"
+            timestampString = "463813473.607358"
             startingColumnNumber = "9223372036854775807"
             endingColumnNumber = "9223372036854775807"
-            startingLineNumber = "310"
-            endingLineNumber = "310"
+            startingLineNumber = "329"
+            endingLineNumber = "329"
             landmarkName = "readWriteTests()"
             landmarkType = "5">
          </BreakpointContent>

swix/swix/swix/ndarray/initing.swift

@@ -99,7 +99,7 @@ func rand(N: Int, distro:String="uniform") -> ndarray{
     let x = zeros(N)
     var i:__CLPK_integer = 1
     if distro=="normal" {i = __CLPK_integer(3)}
-    var seed:Array<__CLPK_integer> = [SWIX_SEED, 0, 0, 0]
+    var seed:Array<__CLPK_integer> = [SWIX_SEED, 2, 3, 5]
     var nn:__CLPK_integer  = __CLPK_integer(N)
     dlarnv_(&i, &seed, &nn, !x)
     SWIX_SEED = seed[0]

swix/swix/swix/tests/tests.swift

@@ -210,7 +210,26 @@ class swixTests {
             assert(copy(arange(4)) ~== arange(4))
             assert(asarray(0..<2) ~== array(0, 1))
             assert(copy(arange(3)) ~== array(0, 1, 2))
-            assert(sum((rand(3) - array(0.516, 0.294, 0.727)) < 1e-2) == 3)
+            //assert(sum((rand(3) - array(0.516, 0.294, 0.727)) < 1e-2) == 3)
+
+            var N = 1e4.int
+            seed(42)
+            var x = rand(N)
+
+            seed(42)
+            var y = rand(N)
+            assert(x ~== y)
+
+            seed(29)
+            y = rand(N)
+            assert(!(x ~== y))
+
+            seed(42)
+            y = rand(N)
+            assert(x ~== y)
+
+            assert(abs(x.mean() - 0.5) < 1e-1)
+            assert(abs(variance(x) - 1/12) < 1e-1)
         }
         func ndarraySwiftTests(){
             // testing the file ndarray.swift