Points getting moved by BezierFunction? Moving an array of
- To: mathgroup at smc.vnet.net
- Subject: [mg118301] Points getting moved by BezierFunction? Moving an array of
- From: "Christopher O. Young" <cy56 at comcast.net>
- Date: Thu, 21 Apr 2011 03:09:35 -0400 (EDT)
Even though all the control points have their maximum x coordinate around 10, the BezierFunction is plotting a long, narrow surface that gets stretched out to x = 40 or so. It may be partly due to the fact that the curves between the points don't start at the x axis and at z = 0 the way I meant them to. Any help for a beginner trying to figure out how to translate each set of points so that it starts with x and y coordinates of zero? That is, I just want to produce a new array for each set of points, where I subtract the x and y coordinates of the first point from each of those points. Thanks in advance for any help. Chris Young cy56 at comcast.net pts = { {{1.796875, 1.34375, -9}, {2.15625, 1.34375, -9}, {2.296875, 1.359375, -9}, {2.375, 1.46875, -9}, {2.46875, 1.671875, -9}, {2.53125, 1.78125, -9}, {2.578125, 1.9375, -9}, {2.6875, 1.96875, -9}, {2.71875, 1.78125, -9}, {2.734375, 1.609375, -9}, {2.921875, 0.421875, -9}, {3.03125, 0.125, -9}, {3.078125, 0.03125, -9}, {3.296875, 0.078125, -9}, {3.484375, 0.0625, -9}, {11.5625, 0, -9}}, {{1.625, 1.171875, -8}, {2.234375, 1.171875, -8}, {2.359375, 1.1875, -8}, {2.5, 1.296875, -8}, {2.765625, 1.421875, -8}, {2.828125, 2.015625, -8}, {2.9375, 2.328125, -8}, {3.1875, 2.34375, -8}, {3.234375, 2, -8}, {3.328125, 1.59375, -8}, {3.453125, 1.234375, -8}, {3.609375, 0.75, -8}, {3.421875, 0.515625, -8}, {3.953125, 0.09375, -8}, {4.234375, 0.203125, -8}, {11.4375, 0.203125, -8}}, {{1.390625, 1.03125, -7}, {2.234375, 1.015625, -7}, {2.46875, 1.0625, -7}, {2.59375, 1.15625, -7}, {2.890625, 1.5625, -7}, {3.15625, 2.1875, -7}, {3.359375, 2.796875, -7}, {3.625, 2.78125, -7}, {3.734375, 2.171875, -7}, {3.90625, 1.46875, -7}, {4.15625, 0.59375, -7}, {4.359375, 0.03125, -7}, {4.453125, 0.15625, -7}, {4.5625, 0.328125, -7}, {5.09375, 0.421875, -7}, {11.171875, 0.390625, -7}}, {{1.203125, 0.875, -6}, {2.328125, 0.84375, -6}, {2.578125, 0.875, -6}, {2.6875, 0.953125, -6}, {3.140625, 1.515625, -6}, {3.4375, 2.15625, -6}, {3.84375, 3.0625, -6}, {4.25, 3.0625, -6}, {4.40625, 2.34375, -6}, {4.65625, 1.625, -6}, {5.0625, 0.515625, -6}, {5.46875, 0.359375, -6}, {5.578125, 0.53125, -6}, {5.84375, 0.5625, -6}, {6.625, 0.59375, -6}, {10.96875, 0.5625, -6}}, {{1, 0.6875, -5}, {2.546875, 0.671875, -5}, {2.734375, 0.71875, -5}, {2.953125, 0.84375, -5}, {3.609375, 1.609375, -5}, {4.0625, 2.578125, -5}, {4.359375, 3.359375, -5}, {4.890625, 3.375, -5}, {5.15625, 2.515625, -5}, {5.5, 1.734375, -5}, {6.0625, 0.484375, -5}, {6.625, 0.390625, -5}, {6.75, 0.59375, -5}, {6.9375, 0.703125, -5}, {8.03125, 0.75, -5}, {10.84375, 0.734375, -5}}, {{0.75, 0.53125, -4}, {3.265625, 0.515625, -4}, {3.390625, 0.546875, -4}, {3.59375, 0.640625, -4}, {3.78125, 0.828125, -4}, {4.25, 1.625, -4}, {5.015625, 3.0625, -4}, {5.40625, 4.15625, -4}, {6.25, 4.140625, -4}, {6.640625, 3.0625, -4}, {7.578125, 1.21875, -4}, {8.234375, 0.40625, -4}, {9.171875, 0.625, -4}, {9.390625, 0.765625, -4}, {9.703125, 0.890625, -4}, {10.546875, 0.875, -4}}, {{0.484375, 0.390625, -3}, {2.984375, 0.34375, -3}, {3.734375, 0.34375, -3}, {3.890625, 0.359375, -3}, {4.046875, 0.375, -3}, {4.265625, 0.453125, -3}, {5.609375, 1.875, -3}, {6.5625, 2.6875, -3}, {6.78125, 2.828125, -3}, {6.984375, 2.890625, -3}, {7.203125, 2.96875, -3}, {8.34375, 3.09375, -3}, {7.46875, 3.046875, -3}, {8.90625, 3.140625, -3}, {9.296875, 3.125, -3}, {10.03125, 3.109375, -3}} {{0.28125, 0.234375, -2}, {1.75, 0.25, -2}, {2.796875, 0.203125, -2}, {3.84375, 0.265625, -2}, {4.625, 0.28125, -2}, {4.875, 0.28125, -2}, {5.046875, 0.328125, -2}, {5.234375, 0.484375, -2}, {6.171875, 1.109375, -2}, {6.796875, 1.578125, -2}, {7.234375, 1.8125, -2}, {7.625, 1.984375, -2}, {7.921875, 2.015625, -2}, {8.1875, 2.046875, -2}, {9.28125, 2.015625, -2}, {9.84375, 2.015625, -2}}, {{0.625, 0.1, -1}, {1.25, 0.1, -1}, {1.875, 0.1, -1}, {2.5, 0.1, -1}, {3.125, 0.1, -1}, {3.75, 0.1, -1}, {4.375, 0.1, -1}, {5, 0.1, -1}, {5.625, 0.1, -1}, {6.25, 0.1, -1}, {6.875, 0.1, -1}, {6.25, 0.1, -1}, {8.125, 0.1, -1}, {8.75, 0.1, -1}, {9.375, 0.1, -1}, {10.265625, 0.109375, -1}} Show[ ParametricPlot3D[ BezierFunction[pts][u, v], {u, 0, 1}, {v, 0, 1}, MeshFunctions -> {#1 &, #3 &}, AxesLabel -> z] ]