1 files changed, 72 insertions, 0 deletions
diff --git a/src/3rdparty/2geom/tests/bezier-sbasis-transforms.py b/src/3rdparty/2geom/tests/bezier-sbasis-transforms.py
new file mode 100644
index 0000000..1dc850f
--- /dev/null
+++ b/src/3rdparty/2geom/tests/bezier-sbasis-transforms.py
@@ -0,0 +1,72 @@
+#!/usr/bin/python
+
+from Numeric import *
+from LinearAlgebra import *
+
+pascals_triangle = []
+rows_done = 0
+
+def choose(n, k):
+    r = 1
+    for i in range(1,k+1):
+        r *= n-k+i
+        r /= i
+    return r
+
+# http://www.research.att.com/~njas/sequences/A109954
+def T(n, k):
+    return ((-1)**(n+k))*choose(n+k+2, 2*k+2)
+
+def inver(q):
+    result = zeros((q+2,q+2))
+    q2 = q/2+1
+    for i in range(q2):
+        for j in range(i+1):
+            val = T(i,j)
+            result[q/2-j][q/2-i] = val
+            result[q/2+j+2][q/2+i+2] = val
+            result[q/2+j+2][q/2-i-1] = -val
+            if q/2+i+3 < q+2:
+                result[q/2-j][q/2+i+3] = -val
+            
+    for i in range(q+2):
+        result[q2][i] = [1,-1][(i-q2)%2]
+    return result
+        
+def simple(q):
+    result = zeros((q+2,q+2))
+    for i in range(q/2+1):
+        for j in range(q+1):
+            result[j][i] = choose(q-2*i, j-i)
+            result[j+1][q-i+1] = choose(q-2*i, j-i)
+    result[q/2+1][q/2+1] = 1
+    return result
+
+print "The aim of the game is to work out the correct indexing to make the two matrices match :)"
+
+s = simple(4)
+si = floor(inverse(s)+0.5)
+print si.astype(Int)
+print inver(4)
+exit(0)
+print "<html><head><title></title></head><body>"
+
+def arrayhtml(a):
+    s = "<table>"
+    r,c = a.shape
+    for i in range(r):
+        s += "<tr>";
+        for j in range(c):
+            s += "<td>%g</td>" % a[i,j]
+        s += "</tr>"
+    s += "</table>"
+    return s
+
+for i in [21]:#range(1,13,2):
+    s = simple(i)
+    print "<h1>T<sup>-1</sup> = </h1>"
+    print arrayhtml(s)
+    print "<h1>T = </h1>"
+    print arrayhtml(floor(inverse(s)+0.5))
+
+print "</body></html>"