我有一组数据，是三维坐标值。x,y,z
x=[ 344.46 349.34 349.27 349.19 349.11 348.94 348.76 348.57 348.36 348.14 347.91 347.67 347.4 347.14 346.85 346.55 346.25 345.93 345.6 345.25 344.9 344.53 344.16 343.77 343.37 342.96 342.54 342.11 341.67 341.22 340.76 340.29 339.82 339.65 339.31 339.57 339.86 340.37 340.87 341.36 341.83 342.28 342.72 343.15 343.57 343.98 344.37 344.74 345.11 345.46 345.79 346.1 346.42 346.72 347 347.27 347.5 347.75 347.97 348.18 348.36 348.54 348.71 348.76 348.16 348.06 347.98 347.9 347.73 347.54 347.33 347.11 346.87 346.62 346.34 346.1 345.8 345.51 345.2 344.88 344.54 344.2 343.83 343.46 343.07 342.69 342.29 341.87 341.44 341 340.55 340.1 339.64 339.17 338.7 338.63 337.91 338.18 338.49 338.75 339.27 339.77 340.26 340.73 341.19 341.64 342.08 342.5 342.89 343.29 343.67 344.04 344.4 344.74 345.06 345.37 345.67 345.94 346.21 346.47 346.69 346.92 347.13 347.32 347.49 ]
y=[ -495.38 -483.24 -483.66 -484.05 -484.5 -485.37 -486.27 -487.14 -488.01 -488.88 -489.74 -490.61 -491.46 -492.32 -493.18 -494.01 -494.85 -495.69 -496.52 -497.36 -498.18 -498.99 -499.81 -500.61 -501.41 -502.21 -503 -503.78 -504.56 -505.33 -506.09 -506.85 -507.61 -507.87 -507.1 -506.66 -506.22 -505.4 -504.56 -503.73 -502.88 -502.04 -501.2 -500.34 -499.49 -498.63 -497.77 -496.9 -496.03 -495.15 -494.26 -493.38 -492.49 -491.59 -490.7 -489.79 -488.9 -487.99 -487.08 -486.17 -485.25 -484.34 -483.41 -483.1 -483.17 -483.58 -484.04 -484.46 -485.36 -486.25 -487.14 -488.01 -488.87 -489.76 -490.58 -491.45 -492.32 -493.17 -494.01 -494.84 -495.67 -496.51 -497.34 -498.16 -498.96 -499.77 -500.57 -501.37 -502.17 -502.95 -503.72 -504.49 -505.25 -506.01 -506.76 -506.86 -506.67 -506.24 -505.79 -505.37 -504.55 -503.73 -502.89 -502.06 -501.22 -500.37 -499.52 -498.66 -497.81 -496.94 -496.08 -495.2 -494.33 -493.44 -492.55 -491.67 -490.77 -489.89 -488.98 -488.08 -487.17 -486.28 -485.36 -484.45 -483.54 ]
z= [ -515.96 -509.36 -509.54 -509.73 -509.92 -510.28 -510.63 -510.99 -511.35 -511.7 -512.06 -512.4 -512.75 -513.1 -513.45 -513.8 -514.13 -514.47 -514.81 -515.15 -515.49 -515.83 -516.16 -516.49 -516.82 -517.14 -517.46 -517.78 -518.1 -518.41 -518.73 -519.03 -519.35 -519.45 -520.23 -520.07 -519.88 -519.54 -519.2 -518.85 -518.51 -518.16 -517.82 -517.47 -517.12 -516.76 -516.41 -516.06 -515.7 -515.35 -514.98 -514.62 -514.26 -513.9 -513.53 -513.16 -512.79 -512.42 -512.05 -511.68 -511.31 -510.93 -510.55 -510.43 -511.55 -511.74 -511.92 -512.09 -512.45 -512.82 -513.18 -513.54 -513.89 -514.25 -514.59 -514.94 -515.29 -515.64 -515.99 -516.33 -516.67 -517 -517.34 -517.68 -518.01 -518.34 -518.66 -518.99 -519.31 -519.64 -519.95 -520.26 -520.58 -520.89 -521.19 -521.23 -522.26 -522.1 -521.89 -521.72 -521.38 -521.04 -520.69 -520.36 -520.02 -519.67 -519.32 -518.96 -518.63 -518.27 -517.92 -517.56 -517.2 -516.84 -516.48 -516.11 -515.75 -515.38 -515.02 -514.65 -514.29 -513.91 -513.54 -513.16 -512.79 ]
能不能直接在matlab上拟合出曲面来啊，要使用哪个函数？


如果不能那么下面的方程

z=a+b*x+c*x^2+d*x^3+e*x^4+f*x^5+g+h*y+i*y^2+j*y^3+k*y^4+l*y^5+m*x*y+n*x^2*y+o*x^3*y+p*x^4*y+q*x*y^4+r*x*y^3+s*x*y^2+t*x^2*y^2+u*x^2*y^3+v*x^3*y^2
能否求出 a b c d e f g h i j k l m n o p q r s t u v 来？这里是已知量为 x y z 的三组数据

我利用for 循环来做可是总是报错，给点意见吧
x=[344.46 349.34 349.27 349.19 349.11 348.94 348.76 348.57 348.36 348.14 347.91 347.67 347.4 347.14 346.85 346.55 346.25 345.93 345.6 345.25 344.9 344.53 344.16 343.77 343.37 342.96 342.54 342.11 341.67 341.22 340.76 340.29 339.82 339.65 339.31 339.57 339.86 340.37 340.87 341.36 341.83 342.28 342.72 343.15 343.57 343.98 344.37 344.74 345.11 345.46 345.79 346.1 346.42 346.72 347 347.27 347.5 347.75 347.97 348.18 348.36 348.54 348.71 348.76 348.16 348.06 347.98 347.9 347.73 347.54 347.33 347.11 346.87 346.62 346.34 346.1 345.8 345.51 345.2 344.88 344.54 344.2 343.83 343.46 343.07 342.69 342.29 341.87 341.44 341 340.55 340.1 339.64 339.17 338.7 338.63 337.91 338.18 338.49 338.75 339.27 339.77 340.26 340.73 341.19 341.64 342.08 342.5 342.89 343.29 343.67 344.04 344.4 344.74 345.06 345.37 345.67 345.94 346.21 346.47 346.69 346.92 347.13 347.32 347.49 347.56
];
y=[-495.38 -483.24 -483.66 -484.05 -484.5 -485.37 -486.27 -487.14 -488.01 -488.88 -489.74 -490.61 -491.46 -492.32 -493.18 -494.01 -494.85 -495.69 -496.52 -497.36 -498.18 -498.99 -499.81 -500.61 -501.41 -502.21 -503 -503.78 -504.56 -505.33 -506.09 -506.85 -507.61 -507.87 -507.1 -506.66 -506.22 -505.4 -504.56 -503.73 -502.88 -502.04 -501.2 -500.34 -499.49 -498.63 -497.77 -496.9 -496.03 -495.15 -494.26 -493.38 -492.49 -491.59 -490.7 -489.79 -488.9 -487.99 -487.08 -486.17 -485.25 -484.34 -483.41 -483.1 -483.17 -483.58 -484.04 -484.46 -485.36 -486.25 -487.14 -488.01 -488.87 -489.76 -490.58 -491.45 -492.32 -493.17 -494.01 -494.84 -495.67 -496.51 -497.34 -498.16 -498.96 -499.77 -500.57 -501.37 -502.17 -502.95 -503.72 -504.49 -505.25 -506.01 -506.76 -506.86 -506.67 -506.24 -505.79 -505.37 -504.55 -503.73 -502.89 -502.06 -501.22 -500.37 -499.52 -498.66 -497.81 -496.94 -496.08 -495.2 -494.33 -493.44 -492.55 -491.67 -490.77 -489.89 -488.98 -488.08 -487.17 -486.28 -485.36 -484.45 -483.54 -483.21
];
z=[-515.96 -509.36 -509.54 -509.73 -509.92 -510.28 -510.63 -510.99 -511.35 -511.7 -512.06 -512.4 -512.75 -513.1 -513.45 -513.8 -514.13 -514.47 -514.81 -515.15 -515.49 -515.83 -516.16 -516.49 -516.82 -517.14 -517.46 -517.78 -518.1 -518.41 -518.73 -519.03 -519.35 -519.45 -520.23 -520.07 -519.88 -519.54 -519.2 -518.85 -518.51 -518.16 -517.82 -517.47 -517.12 -516.76 -516.41 -516.06 -515.7 -515.35 -514.98 -514.62 -514.26 -513.9 -513.53 -513.16 -512.79 -512.42 -512.05 -511.68 -511.31 -510.93 -510.55 -510.43 -511.55 -511.74 -511.92 -512.09 -512.45 -512.82 -513.18 -513.54 -513.89 -514.25 -514.59 -514.94 -515.29 -515.64 -515.99 -516.33 -516.67 -517 -517.34 -517.68 -518.01 -518.34 -518.66 -518.99 -519.31 -519.64 -519.95 -520.26 -520.58 -520.89 -521.19 -521.23 -522.26 -522.1 -521.89 -521.72 -521.38 -521.04 -520.69 -520.36 -520.02 -519.67 -519.32 -518.96 -518.63 -518.27 -517.92 -517.56 -517.2 -516.84 -516.48 -516.11 -515.75 -515.38 -515.02 -514.65 -514.29 -513.91 -513.54 -513.16 -512.79 -512.66
];
syms a b c d e f g h i j k l m n o p q r s t u;
B=[a b c d e f g h i j k l m n o p q r s t u]';
for i=1:126;
A(i)=[1,x(i),x(i)^2,x(i)^3,x(i)^4,x(i)^5,y(i),y(i)^2,y(i)^3,y(i)^4,y(i)^5,x(i)*y(i),x(i)*y(i)^2,x(i)*y(i)^3,x(i)*y(i)^4,x(i)^2*y(i),x(i)^2*y(i)^2,x(i)^2*y(i)^3,x(i)^3*y(i),x(i)^3*y(i)^2,x(i)^4*y(i)];
B=A\z
end;
??? In an assignment A(I) = B, the number of elements in B and
I must be the same.

syms a b c d e f g h i j k l m n o p q r s t u;
B=[a b c d e f g h i j k l m n o p q r s t u]';
for i=1:126;
A(i,:)=[1,x(i),x(i)^2,x(i)^3,x(i)^4,x(i)^5,y(i),y(i)^2,y(i)^3,y(i)^4,y(i)^5,x(i)*y(i),x(i)*y(i)^2,x(i)*y(i)^3,x(i)*y(i)^4,x(i)^2*y(i),x(i)^2*y(i)^2,x(i)^2*y(i)^3,x(i)^3*y(i),x(i)^3*y(i)^2,x(i)^4*y(i)];
B=regress(z',A)
end;

更正 for i=1:125;

可以直接用1stopt进行拟合，自动选择公式

Title "Type your title here";
Variable x1,x2;
variable y;
data;
344.46 -495.38 -515.96
349.34 -483.24 -509.36
349.27 -483.66 -509.54
349.19 -484.05 -509.73
349.11 -484.5 -509.92
348.94 -485.37 -510.28
348.76 -486.27 -510.63
348.57 -487.14 -510.99
348.36 -488.01 -511.35
348.14 -488.88 -511.7
347.91 -489.74 -512.06
347.67 -490.61 -512.4
347.4 -491.46 -512.75
347.14 -492.32 -513.1
346.85 -493.18 -513.45
346.55 -494.01 -513.8
346.25 -494.85 -514.13
345.93 -495.69 -514.47
345.6 -496.52 -514.81
345.25 -497.36 -515.15
344.9 -498.18 -515.49
344.53 -498.99 -515.83
344.16 -499.81 -516.16
343.77 -500.61 -516.49
343.37 -501.41 -516.82
342.96 -502.21 -517.14
342.54 -503 -517.46
342.11 -503.78 -517.78
341.67 -504.56 -518.1
341.22 -505.33 -518.41
340.76 -506.09 -518.73
340.29 -506.85 -519.03
339.82 -507.61 -519.35
339.65 -507.87 -519.45
339.31 -507.1 -520.23
339.57 -506.66 -520.07
339.86 -506.22 -519.88
340.37 -505.4 -519.54
340.87 -504.56 -519.2
341.36 -503.73 -518.85
341.83 -502.88 -518.51
342.28 -502.04 -518.16
342.72 -501.2 -517.82
343.15 -500.34 -517.47
343.57 -499.49 -517.12
343.98 -498.63 -516.76
344.37 -497.77 -516.41
344.74 -496.9 -516.06
345.11 -496.03 -515.7
345.46 -495.15 -515.35
345.79 -494.26 -514.98
346.1 -493.38 -514.62
346.42 -492.49 -514.26
346.72 -491.59 -513.9
347 -490.7 -513.53
347.27 -489.79 -513.16
347.5 -488.9 -512.79
347.75 -487.99 -512.42
347.97 -487.08 -512.05
348.18 -486.17 -511.68
348.36 -485.25 -511.31
348.54 -484.34 -510.93
348.71 -483.41 -510.55
348.76 -483.1 -510.43
348.16 -483.17 -511.55
348.06 -483.58 -511.74
347.98 -484.04 -511.92
347.9 -484.46 -512.09
347.73 -485.36 -512.45
347.54 -486.25 -512.82
347.33 -487.14 -513.18
347.11 -488.01 -513.54
346.87 -488.87 -513.89
346.62 -489.76 -514.25
346.34 -490.58 -514.59
346.1 -491.45 -514.94
345.8 -492.32 -515.29
345.51 -493.17 -515.64
345.2 -494.01 -515.99
344.88 -494.84 -516.33
344.54 -495.67 -516.67
344.2 -496.51 -517
343.83 -497.34 -517.34
343.46 -498.16 -517.68
343.07 -498.96 -518.01
342.69 -499.77 -518.34
342.29 -500.57 -518.66
341.87 -501.37 -518.99
341.44 -502.17 -519.31
341 -502.95 -519.64
340.55 -503.72 -519.95
340.1 -504.49 -520.26
339.64 -505.25 -520.58
339.17 -506.01 -520.89
338.7 -506.76 -521.19
338.63 -506.86 -521.23
337.91 -506.67 -522.26
338.18 -506.24 -522.1
338.49 -505.79 -521.89
338.75 -505.37 -521.72
339.27 -504.55 -521.38
339.77 -503.73 -521.04
340.26 -502.89 -520.69
340.73 -502.06 -520.36
341.19 -501.22 -520.02
341.64 -500.37 -519.67
342.08 -499.52 -519.32
342.5 -498.66 -518.96
342.89 -497.81 -518.63
343.29 -496.94 -518.27
343.67 -496.08 -517.92
344.04 -495.2 -517.56
344.4 -494.33 -517.2
344.74 -493.44 -516.84
345.06 -492.55 -516.48
345.37 -491.67 -516.11
345.67 -490.77 -515.75
345.94 -489.89 -515.38
346.21 -488.98 -515.02
346.47 -488.08 -514.65
346.69 -487.17 -514.29
346.92 -486.28 -513.91
347.13 -485.36 -513.54
347.32 -484.45 -513.16
347.49 -483.54 -512.79

计算结果：

Function: z = p1+p2*x+p3*x^2+p4*x^3+p5*y+p6*y^2+p7*y^3

Algorithms: 麦夸特法(Levenberg-Marquardt) + 通用全局优化法
Root of Mean Square Error (RMSE): 0.0822015342100493
Sum of Square Error (SSE): 0.844636528310737
Correlation Coef. (R): 0.99968803592071
R-Square: 0.999376169163008
Determination Coef. (DC): 0.999376169163006

p1 -21701.3892998997
p2 330.39486259529
p3 -0.982891146759383
p4 0.000978421697292379
p5 91.7795063651202
p6 0.174626752351192
p7 0.000110043776398182