diff --git a/geometry.py b/geometry.py
index 38dd050..ff9c396 100755
--- a/geometry.py
+++ b/geometry.py
@@ -176,23 +176,23 @@ class geometry:
     # [pxx pxy]
     # [pyx pyy]
     #
-    # [a b] [mx] [px]
+    # [a b] [px] [mx]
     # [   ]*[  ]=[  ]
-    # [c d] [my] [py]
+    # [c d] [py] [my]
     #
-    # [a*mx1  b*my1]  [px1]
+    # [a*px1  b*py1]  [mx1]
     # [  ...   ... ]  [...]
-    # [a*mxn  b*myn] =[pxn]
-    # [c*mx1  d*my1]  [py1]
+    # [a*pxn  b*pyn] =[mxn]
+    # [c*px1  d*py1]  [my1]
     # [  ...   ... ]  [...]
-    # [c*mxn  d*myn]  [pyn]
+    # [c*pxn  d*pyn]  [myn]
     #
-    # [mx1 my1   0   0 ] [a] [px1]
+    # [px1 py1   0   0 ] [a] [mx1]
     # [... ..    0   0 ] [b] [...]
-    # [mxn myn   0   0 ]*[c]=[pxn]
-    # [ 0   0   mx1 my1] [d] [py1]
+    # [pxn pyn   0   0 ]*[c]=[mxn]
+    # [ 0   0   px1 py1] [d] [my1]
     # [ 0   0   ... .. ]     [...]
-    # [ 0   0   mxn myn]     [pyn]
+    # [ 0   0   pxn pyn]     [myn]
     #
     #          A        *aa = y
 
@@ -228,9 +228,9 @@ class geometry:
       d=m[1:]-m[0]  # distances
 
       A=np.zeros((d.shape[0]*2, d.shape[1]), np.float)
-      A[:d.shape[0], :2]=A[d.shape[0]:, 2:]=d[:, :2]
+      A[:d.shape[0], :2]=A[d.shape[0]:, 2:]=d[:, 2:]
 
-      y=d[:, 2:].T.ravel()
+      y=d[:, :2].T.ravel()
       y=np.asmatrix(y).T
       A=np.asmatrix(A)
 
@@ -321,6 +321,8 @@ if __name__=="__main__":
 
     obj.update_pix2pos(measure)
     obj.interp_zoom(1)
+    print(obj._pix2pos)
+    print(obj._pix2pos.I)
     obj.interp_zoom(200)
     obj.interp_zoom(100)