1stopt多条曲线拟合，得不到好的结果。

tcwave

在1.5版本里面编的，结果根本不对。

以下是程序，不知道程序是否有问题。
Title "para-extract3";
parameters a(1:8);
ParameterDomain = [0, ];
Variables x,y1[Output],y2[Output],y3[Output];
StartProgram;
var i: integer;
begin
    for i := 0 to DataLength - 1 do begin
    y1:= 20*log(a1/sqrt((a1-(2*pi*x)^2*1E-21)^2+(2*pi*x*a2*1E-11)^2))-20*log(a3/sqrt((a3-(2*pi*x)^2*1E-21)^2+(2*pi*x*a4*1E-11)^2));
    y2:= 20*log(a5/sqrt((a5-(2*pi*x)^2*1E-21)^2+(2*pi*x*a6*1E-11)^2))-20*log(a3/sqrt((a3-(2*pi*x)^2*1E-21)^2+(2*pi*x*a4*1E-11)^2));
    y3:= 20*log(a7/sqrt((a7-(2*pi*x)^2*1E-21)^2+(2*pi*x*a8*1E-11)^2))-20*log(a3/sqrt((a3-(2*pi*x)^2*1E-21)^2+(2*pi*x*a4*1E-11)^2));
    end;
end;
EndProgram;
Data;
// x             y1                 y2             y3
1000000000 0.002551834 -0.006703704 -0.01130098
1200000000 0.004921394 -0.009305916 -0.014890081
1400000000 0.009599757 -0.011895226 -0.019692177
1600000000 0.01427812 -0.014394487 -0.024683452
1800000000 0.023840487 -0.01672655 -0.02893692
2000000000 0.035356456 -0.018814267 -0.033101704
2200000000 0.046872426 -0.020469738 -0.037203382
2400000000 0.057720058 -0.021572457 -0.041873808
2600000000 0.070719619 -0.025708877 -0.050418187
2800000000 0.083719179 -0.02934049 -0.058790011
3000000000 0.09671874 -0.032938812 -0.066955267
3200000000 0.114220516 -0.038593364 -0.076915333
3400000000 0.129576736 -0.048721665 -0.091573543
3600000000 0.144932956 -0.058343962 -0.106231753
3800000000 0.165690124 -0.067180269 -0.120889963
4000000000 0.188607671 -0.075015534 -0.135548173
4200000000 0.211525219 -0.081936004 -0.150191665
4400000000 0.247104814 -0.08892723 -0.165432488
4600000000 0.279868818 -0.100352548 -0.185472266
4800000000 0.312815096 -0.111286391 -0.205322341
5000000000 0.345834283 -0.121540725 -0.22506073
5200000000 0.37885347 -0.130731728 -0.244765451
5400000000 0.41389011 -0.1431159 -0.268519078
5600000000 0.441471861 -0.160247282 -0.297547692
5800000000 0.456865801 -0.176900433 -0.326427972
6000000000 0.441350649 -0.19288417 -0.355169354
6200000000 0.403557654 -0.210607858 -0.386413309
6400000000 0.350591631 -0.22802905 -0.41797591
6600000000 0.252813853 -0.244859986 -0.44942792
6800000000 0.143911846 -0.260973072 -0.48077665
7000000000 0.004582623 -0.278603364 -0.514520178
7200000000 -0.14012654 -0.293830697 -0.546095567
7400000000 -0.278121878 -0.299553707 -0.567784887
7600000000 -0.401385281 -0.303769698 -0.587493103
7800000000 -0.51016835 -0.295568861 -0.594654763
8000000000 -0.596536797 -0.276190476 -0.588815828
8200000000 -0.666233766 -0.245686104 -0.569470315
8400000000 -0.735930736 -0.216507414 -0.549602024
8600000000 -0.75036075 -0.155934279 -0.496147476
8800000000 -0.759403559 -0.093350722 -0.440978257
9000000000 -0.758056758 -0.024756068 -0.375706212
9200000000 -0.755244755 0.036130817 -0.309525604
9400000000 -0.73017353 0.100580922 -0.234974666
9600000000 -0.702680484 0.162286477 -0.157756085
9800000000 -0.661786698 0.220200637 -0.074810504
10000000000 -0.619027213 0.265265853 -0.000765045
10200000000 -0.579439416 0.298370608 0.068494468
10400000000 -0.539851619 0.327208594 0.136732403
10600000000 -0.500263821 0.354669542 0.204970338
10800000000 -0.473451397 0.366278191 0.259937948
11000000000 -0.448768201 0.372672253 0.31030446
11200000000 -0.424085006 0.373973825 0.358583272
11400000000 -0.407713499 0.361647851 0.397146195
11600000000 -0.391341991 0.349441033 0.434988419
11800000000 -0.38291548 0.334553787 0.463775607
12000000000 -0.374488969 0.322782381 0.489305109
12200000000 -0.372136954 0.306701184 0.506275881
12400000000 -0.374340811 0.288325768 0.517155262
12600000000 -0.376544667 0.272708952 0.527447836
12800000000 -0.378748524 0.260282341 0.537126979
13000000000 -0.380952381 0.250291445 0.545124791
13200000000 -0.383156238 0.242412103 0.551731897
13400000000 -0.385360094 0.236690192 0.557263863
13600000000 -0.387563951 0.23317159 0.562036251
13800000000 -0.389767808 0.23178399 0.566346272
14000000000 -0.391971665 0.232085102 0.569440717

tcwave

是不是在网上下的那个版本根本不行呀！
请大家帮帮忙，或者帮我算下，或者给点建议！

dingd

网上的1.5版好像不能运行这种编程模式。

tcwave

那该怎么办阿！写成其他的模式可以吗？

dingd能帮我运行下看看吗？

dingd

参数                  最佳估算
--------------------        -------------
a1                 2.77268756829831
a2                 2.10066454582647
a3                 2.84837382022405
a4                 2.02318105315998
a5                 2.92069844517101
a6                 2.10784104172287
a7                 2.96201237628006
a8                 2.23343909638757

tcwave

thank u very much!