More than 25 parameters in Minuit

ROOT
1

Hi
I want to fit using 28 parameters in Minuit. After looking at past roottalk sessions I found that you had to include TVirtualFitter to get rid of the limit of 25 parameters. Also it seemed that you might need BuildArrays to get sufficient array sizes. So I have the attached code.
Now it runs but it only seems to minimise 15 parameters (without the TVirtualFitter and BuildArrays it successfully minimises 24 parameters). The output is also attached below.
Do I need to set something else to get it to minimise more than 25 parameters?
Thanks
Peter Litchfield

TMinuit *gMinuit = new TMinuit(2);
TVirtualFitter::Fitter(0,50);

gMinuit->SetFCN(fcnli);
Int_t maxpar=30;
gMinuit->BuildArrays(maxpar);

** 1 **SET ERR 1

PARAMETER DEFINITIONS:
NO. NAME VALUE STEP SIZE LIMITS
1 slope pmtA - pmtB 1.00000e+00 3.00000e-01 no limits
2 slope pmtA - pinAl 1.00000e+00 3.00000e-01 no limits
3 slope pmtA - pinAh 1.00000e+00 3.00000e-01 no limits
4 slope pmtB - pinAl 1.00000e+00 3.00000e-01 no limits
5 slope pmtB - pinAh 1.00000e+00 3.00000e-01 no limits
6 slope pmtB - pmtA 1.00000e+00 3.00000e-01 no limits
7 slope pmtB - pinBl 1.00000e+00 3.00000e-01 no limits
8 slope pmtB - pinBh 1.00000e+00 3.00000e-01 no limits
9 slope pmtB - pinAl 1.00000e+00 3.00000e-01 no limits
10 slope pmtA - pinAh 1.00000e+00 3.00000e-01 no limits
11 slope pinAl - pinAh 1.00000e+00 3.00000e-01 no limits
12 slope pinBl - pinBh 1.00000e+00 3.00000e-01 no limits
13 curvature pmtA 0.00000e+00 3.00000e-05 no limits
14 curvature pmtB 0.00000e+00 3.00000e-05 no limits
15 curvature pinAl 0.00000e+00 3.00000e-05 no limits
16 curvature pinAh 0.00000e+00 3.00000e-05 no limits
17 curvature pinBl 0.00000e+00 3.00000e-05 no limits
18 curvature pinBh 0.00000e+00 3.00000e-05 no limits
19 curvature pmtA 0.00000e+00 3.00000e-09 no limits
20 curvature pmtB 0.00000e+00 3.00000e-09 no limits
21 curvature pinAl 0.00000e+00 3.00000e-09 no limits
22 curvature pinAh 0.00000e+00 3.00000e-09 no limits
23 curvature pinBl 0.00000e+00 3.00000e-09 no limits
24 curvature pinBh 0.00000e+00 3.00000e-09 no limits
25 curvature pmtA 0.00000e+00 3.00000e-13 no limits
26 curvature pmtB 0.00000e+00 3.00000e-13 no limits
27 curvature pinAl 0.00000e+00 3.00000e-13 no limits
28 curvature pinAh 0.00000e+00 3.00000e-13 no limits

** 2 **CALL FCN 1

** 3 **MIGRAD 1e+05 1

FIRST CALL TO USER FUNCTION AT NEW START POINT, WITH IFLAG=4.
START MIGRAD MINIMIZATION. STRATEGY 1. CONVERGENCE WHEN EDM .LT. 1.00e-03
FCN=8.3097e+06 FROM MIGRAD STATUS=INITIATE 223 CALLS 225 TOTAL
EDM= unknown STRATEGY= 1 NO ERROR MATRIX
EXT PARAMETER CURRENT GUESS STEP FIRST
NO. NAME VALUE ERROR SIZE DERIVATIVE
1 slope pmtA - pmtB 1.04493e-01 3.00000e-01 0.00000e+00 1.44806e+05
2 slope pmtA - pinAl 1.00000e+00 3.00000e-01 0.00000e+00 -1.48374e+05
3 slope pmtA - pinAh 1.00000e+00 3.00000e-01 0.00000e+00 -3.90722e+05
4 slope pmtB - pinAl 1.00000e+00 3.00000e-01 0.00000e+00 -8.47927e+04
5 slope pmtB - pinAh 1.00000e+00 3.00000e-01 0.00000e+00 1.16627e+06
6 slope pmtB - pmtA 2.94198e-01 3.00000e-01 0.00000e+00 9.70807e+05
7 slope pmtB - pinBl 1.00000e+00 3.00000e-01 0.00000e+00 -1.88076e+05
8 slope pmtB - pinBh 1.00000e+00 3.00000e-01 0.00000e+00 -4.39675e+05
9 slope pmtB - pinAl 1.00000e+00 3.00000e-01 0.00000e+00 -1.14379e+05
10 slope pmtA - pinAh 1.00000e+00 3.00000e-01 0.00000e+00 -8.97751e+04
11 slope pinAl - pinAh 3.64594e-01 3.00000e-01 0.00000e+00 1.12031e+08
12 slope pinBl - pinBh 4.19732e-01 3.00000e-01 -5.80268e-01 2.42308e+07
13 curvature pmtA 0.00000e+00 3.00000e-05 0.00000e+00 3.34800e+10
14 curvature pmtB 0.00000e+00 3.00000e-05 0.00000e+00 5.64450e+10
15 curvature pinAl 0.00000e+00 3.00000e-05 0.00000e+00 -3.24301e+10
16 curvature pinAh 0.00000e+00 3.00000e-05 3.00000e-05 6.66667e+04
17 curvature pinBl 0.00000e+00 3.00000e-05 3.00000e-05 6.66667e+04
18 curvature pinBh 0.00000e+00 3.00000e-05 3.00000e-05 6.66667e+04
19 curvature pmtA 0.00000e+00 3.00000e-09 3.00000e-09 6.66667e+08
20 curvature pmtB 0.00000e+00 3.00000e-09 3.00000e-09 6.66667e+08
21 curvature pinAl 0.00000e+00 3.00000e-09 3.00000e-09 6.66667e+08
22 curvature pinAh 0.00000e+00 3.00000e-09 3.00000e-09 6.66667e+08
23 curvature pinBl 0.00000e+00 3.00000e-09 3.00000e-09 6.66667e+08
24 curvature pinBh 0.00000e+00 3.00000e-09 3.00000e-09 6.66667e+08
25 curvature pmtA 0.00000e+00 3.00000e-13 3.00000e-13 6.66667e+12
26 curvature pmtB 0.00000e+00 3.00000e-13 3.00000e-13 6.66667e+12
27 curvature pinAl 0.00000e+00 3.00000e-13 3.00000e-13 6.66667e+12
28 curvature pinAh 0.00000e+00 3.00000e-13 3.00000e-13 6.66667e+12
MIGRAD MINIMIZATION HAS CONVERGED.
MIGRAD WILL VERIFY CONVERGENCE AND ERROR MATRIX.
EIGENVALUES OF SECOND-DERIVATIVE MATRIX:
-2.2740e+03 -1.2121e+03 -8.4926e+02 -3.2432e+02 -2.0276e+02 -9.3444e+01 9.9995e-01 1.0643e+02 1.9863e+02 2.0760e+02 2.7763e+02 8.2706e+02 1.0664e+03 1.8035e+03 6.9272e+03
MINUIT WARNING IN HESSE
============== MATRIX FORCED POS-DEF BY ADDING 2280.965965 TO DIAGONAL.
MINUIT WARNING IN HESSE
============== Matrix inversion fails.
MNHESS FAILS AND WILL RETURN DIAGONAL MATRIX.
FCN=73263 FROM MIGRAD STATUS=CONVERGED 876 CALLS 878 TOTAL
EDM=5.87681e-06 STRATEGY= 1 ERROR MATRIX UNCERTAINTY 100.0 per cent
EXT PARAMETER APPROXIMATE STEP FIRST
NO. NAME VALUE ERROR SIZE DERIVATIVE
1 slope pmtA - pmtB 9.77496e-02 3.10973e-04 4.10969e-05 1.86548e+00
2 slope pmtA - pinAl 1.42956e+01 1.34222e-02 1.77394e-03 2.97568e-02
3 slope pmtA - pinAh 4.59557e+00 4.29321e-03 5.67411e-04 8.41541e-02
4 slope pmtB - pinAl 1.39748e+00 3.03236e-03 4.00770e-04 8.74774e-02
5 slope pmtB - pinAh 4.49020e-01 9.72793e-04 1.28569e-04 7.50247e-01
6 slope pmtB - pmtA 1.74756e-01 3.91527e-04 5.17425e-05 4.06903e+00
7 slope pmtB - pinBl 1.87661e+01 1.34731e-02 1.78067e-03 1.32149e-02
8 slope pmtB - pinBh 7.29623e+00 5.23623e-03 6.92044e-04 3.30278e-03
9 slope pmtB - pinAl 3.27271e+00 6.31156e-03 8.34165e-04 -9.30409e-02
10 slope pmtA - pinAh 1.26710e+00 2.43970e-03 3.22442e-04 -1.03948e-02
11 slope pinAl - pinAh 3.21445e-01 2.54491e-05 3.36349e-06 -1.18811e+02
12 slope pinBl - pinBh 3.84429e-01 5.03368e-05 6.65276e-06 2.76011e+01
13 curvature pmtA 1.57537e-07 7.34350e-08 9.70556e-09 -7.23758e+03
14 curvature pmtB 7.13089e-06 5.82131e-08 7.69375e-09 1.88577e+03
15 curvature pinAl 6.21879e-06 9.09072e-08 1.20148e-08 3.21677e+04
16 curvature pinAh 0.00000e+00 3.00000e-05 3.00000e-05 6.66667e+04
17 curvature pinBl 0.00000e+00 3.00000e-05 3.00000e-05 6.66667e+04
18 curvature pinBh 0.00000e+00 3.00000e-05 3.00000e-05 6.66667e+04
19 curvature pmtA 0.00000e+00 3.00000e-09 3.00000e-09 6.66667e+08
20 curvature pmtB 0.00000e+00 3.00000e-09 3.00000e-09 6.66667e+08
21 curvature pinAl 0.00000e+00 3.00000e-09 3.00000e-09 6.66667e+08
22 curvature pinAh 0.00000e+00 3.00000e-09 3.00000e-09 6.66667e+08
23 curvature pinBl 0.00000e+00 3.00000e-09 3.00000e-09 6.66667e+08
24 curvature pinBh 0.00000e+00 3.00000e-09 3.00000e-09 6.66667e+08
25 curvature pmtA 0.00000e+00 3.00000e-13 3.00000e-13 6.66667e+12
26 curvature pmtB 0.00000e+00 3.00000e-13 3.00000e-13 6.66667e+12
27 curvature pinAl 0.00000e+00 3.00000e-13 3.00000e-13 6.66667e+12
28 curvature pinAh 0.00000e+00 3.00000e-13 3.00000e-13 6.66667e+12
EXTERNAL ERROR MATRIX. NDIM= 25 NPAR= 15 ERR DEF=1
ELEMENTS ABOVE DIAGONAL ARE NOT PRINTED.
9.670e-08
0.000e+00 1.802e-04
0.000e+00 0.000e+00 1.843e-05
0.000e+00 0.000e+00 0.000e+00 9.195e-06
0.000e+00 0.000e+00 0.000e+00 0.000e+00 9.463e-07
0.000e+00 0.000e+00 0.000e+00 0.000e+00 0.000e+00 1.533e-07
0.000e+00 0.000e+00 0.000e+00 0.000e+00 0.000e+00 0.000e+00 1.815e-04
0.000e+00 0.000e+00 0.000e+00 0.000e+00 0.000e+00 0.000e+00 0.000e+002.742e-05
0.000e+00 0.000e+00 0.000e+00 0.000e+00 0.000e+00 0.000e+00 0.000e+000.000e+00 3.984e-05
0.000e+00 0.000e+00 0.000e+00 0.000e+00 0.000e+00 0.000e+00 0.000e+000.000e+00 0.000e+00 5.952e-06
0.000e+00 0.000e+00 0.000e+00 0.000e+00 0.000e+00 0.000e+00 0.000e+000.000e+00 0.000e+00 0.000e+00 6.477e-10
0.000e+00 0.000e+00 0.000e+00 0.000e+00 0.000e+00 0.000e+00 0.000e+000.000e+00 0.000e+00 0.000e+00 0.000e+00
0.000e+00 0.000e+00 0.000e+00 0.000e+00 0.000e+00 0.000e+00 0.000e+000.000e+00 0.000e+00 0.000e+00 0.000e+00 2.534e-09
0.000e+00 0.000e+00 0.000e+00 0.000e+00 0.000e+00 0.000e+00 0.000e+000.000e+00 0.000e+00 0.000e+00 0.000e+00
0.000e+00 0.000e+00 0.000e+00 0.000e+00 0.000e+00 0.000e+00 0.000e+000.000e+00 0.000e+00 0.000e+00 0.000e+00 0.000e+00 5.393e-15
0.000e+00 0.000e+00 0.000e+00 0.000e+00 0.000e+00 0.000e+00 0.000e+000.000e+00 0.000e+00 0.000e+00 0.000e+00
0.000e+00 0.000e+00 0.000e+00 0.000e+00 0.000e+00 0.000e+00 0.000e+000.000e+00 0.000e+00 0.000e+00 0.000e+00 0.000e+00 0.000e+00 3.389e-15
0.000e+00 0.000e+00 0.000e+00 0.000e+00 0.000e+00 0.000e+00 0.000e+000.000e+00 0.000e+00 0.000e+00 0.000e+00
0.000e+00 0.000e+00 0.000e+00 0.000e+00 0.000e+00 0.000e+00 0.000e+000.000e+00 0.000e+00 0.000e+00 0.000e+00 0.000e+00 0.000e+00 0.000e+00 8.264e-15
ERR MATRIX APPROXIMATE
PARAMETER CORRELATION COEFFICIENTS
NO. GLOBAL 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15
1 0.00000 1.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000
2 0.00000 0.000 1.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000
3 0.00000 0.000 0.000 1.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000
4 0.00000 0.000 0.000 0.000 1.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000
5 0.00000 0.000 0.000 0.000 0.000 1.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000
6 0.00000 0.000 0.000 0.000 0.000 0.000 1.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000
7 0.00000 0.000 0.000 0.000 0.000 0.000 0.000 1.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000
8 0.00000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 1.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000
9 0.00000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 1.000 0.000 0.000 0.000 0.000 0.000 0.000
10 0.00000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 1.000 0.000 0.000 0.000 0.000 0.000
11 0.00000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 1.000 0.000 0.000 0.000 0.000
12 0.00000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 1.000 0.000 0.000 0.000
13 0.00000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 1.000 0.000 0.000
14 0.00000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 1.000 0.000
15 0.00000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 1.000
ERR MATRIX APPROXIMATE

2

Instead of:

[code]TMinuit *gMinuit = new TMinuit(2);
TVirtualFitter::Fitter(0,50);

gMinuit->SetFCN(fcnli);
Int_t maxpar=30;
gMinuit->BuildArrays(maxpar); [/code]
do

Rene

3

Hi Rene
I assume I still need the definition of gMinuit and fcn but when I leave out the call to BuildArrays it only fits 25 parameters, see output.
Peter

** 1 **SET ERR 1

PARAMETER DEFINITIONS:
NO. NAME VALUE STEP SIZE LIMITS
1 slope pmtA - pmtB 1.00000e+00 3.00000e-01 no limits
2 slope pmtA - pinAl 1.00000e+00 3.00000e-01 no limits
3 slope pmtA - pinAh 1.00000e+00 3.00000e-01 no limits
4 slope pmtB - pinAl 1.00000e+00 3.00000e-01 no limits
5 slope pmtB - pinAh 1.00000e+00 3.00000e-01 no limits
6 slope pmtB - pmtA 1.00000e+00 3.00000e-01 no limits
7 slope pmtB - pinBl 1.00000e+00 3.00000e-01 no limits
8 slope pmtB - pinBh 1.00000e+00 3.00000e-01 no limits
9 slope pmtB - pinAl 1.00000e+00 3.00000e-01 no limits
10 slope pmtA - pinAh 1.00000e+00 3.00000e-01 no limits
11 slope pinAl - pinAh 1.00000e+00 3.00000e-01 no limits
12 slope pinBl - pinBh 1.00000e+00 3.00000e-01 no limits
13 curvature pmtA 0.00000e+00 3.00000e-05 no limits
14 curvature pmtB 0.00000e+00 3.00000e-05 no limits
15 curvature pinAl 0.00000e+00 3.00000e-05 no limits
16 curvature pinAh 0.00000e+00 3.00000e-05 no limits
17 curvature pinBl 0.00000e+00 3.00000e-05 no limits
18 curvature pinBh 0.00000e+00 3.00000e-05 no limits
19 curvature pmtA 0.00000e+00 3.00000e-09 no limits
20 curvature pmtB 0.00000e+00 3.00000e-09 no limits
21 curvature pinAl 0.00000e+00 3.00000e-09 no limits
22 curvature pinAh 0.00000e+00 3.00000e-09 no limits
23 curvature pinBl 0.00000e+00 3.00000e-09 no limits
24 curvature pinBh 0.00000e+00 3.00000e-09 no limits
25 curvature pmtA 0.00000e+00 3.00000e-13 no limits
26 curvature pmtB 0.00000e+00 3.00000e-13 no limits
MINUIT USER ERROR. TOO MANY VARIABLE PARAMETERS.
27 curvature pinAl 0.00000e+00 3.00000e-13 no limits
MINUIT USER ERROR. TOO MANY VARIABLE PARAMETERS.
28 curvature pinAh 0.00000e+00 3.00000e-13 no limits
MINUIT USER ERROR. TOO MANY VARIABLE PARAMETERS.

** 2 **CALL FCN 1

** 3 **MIGRAD 1e+05 1

FIRST CALL TO USER FUNCTION AT NEW START POINT, WITH IFLAG=4.
START MIGRAD MINIMIZATION. STRATEGY 1. CONVERGENCE WHEN EDM .LT. 1.00e-03
FCN=7.14705e+06 FROM MIGRAD STATUS=INITIATE 351 CALLS 353 TOTAL
EDM= unknown STRATEGY= 1 NO ERROR MATRIX
EXT PARAMETER CURRENT GUESS STEP FIRST
NO. NAME VALUE ERROR SIZE DERIVATIVE
1 slope pmtA - pmtB 1.57363e-01 3.00000e-01 0.00000e+00 1.11953e+04
2 slope pmtA - pinAl 1.00000e+00 3.00000e-01 0.00000e+00 -9.86092e+04
3 slope pmtA - pinAh 1.00000e+00 3.00000e-01 0.00000e+00 -2.77490e+05
4 slope pmtB - pinAl 1.00000e+00 3.00000e-01 0.00000e+00 -1.48365e+05
5 slope pmtB - pinAh 1.00000e+00 3.00000e-01 0.00000e+00 -3.41805e+04
6 slope pmtB - pmtA 1.52019e-01 3.00000e-01 0.00000e+00 3.99989e+05
7 slope pmtB - pinBl 1.00000e+00 3.00000e-01 0.00000e+00 -4.01150e+04
8 slope pmtB - pinBh 1.00000e+00 3.00000e-01 0.00000e+00 -9.52038e+04
9 slope pmtB - pinAl 1.00000e+00 3.00000e-01 0.00000e+00 -1.29313e+05
10 slope pmtA - pinAh 1.00000e+00 3.00000e-01 0.00000e+00 -1.26221e+05
11 slope pinAl - pinAh 3.67799e-01 3.00000e-01 0.00000e+00 1.18204e+08
12 slope pinBl - pinBh 4.28548e-01 3.00000e-01 -5.71452e-01 2.92413e+07
13 curvature pmtA 0.00000e+00 3.00000e-05 0.00000e+00 3.54587e+10
14 curvature pmtB 0.00000e+00 3.00000e-05 0.00000e+00 2.27654e+10
15 curvature pinAl 0.00000e+00 3.00000e-05 0.00000e+00 -3.43792e+10
16 curvature pinAh 0.00000e+00 3.00000e-05 0.00000e+00 1.22818e+11
17 curvature pinBl 0.00000e+00 3.00000e-05 0.00000e+00 -7.15187e+09
18 curvature pinBh 0.00000e+00 3.00000e-05 0.00000e+00 2.10036e+10
19 curvature pmtA 0.00000e+00 3.00000e-09 0.00000e+00 3.30944e+14
20 curvature pmtB 0.00000e+00 3.00000e-09 0.00000e+00 2.00461e+14
21 curvature pinAl 0.00000e+00 3.00000e-09 0.00000e+00 -3.14311e+13
22 curvature pinAh 0.00000e+00 3.00000e-09 0.00000e+00 3.53050e+14
23 curvature pinBl 0.00000e+00 3.00000e-09 0.00000e+00 -4.45827e+12
24 curvature pinBh 0.00000e+00 3.00000e-09 0.00000e+00 3.52905e+13
25 curvature pmtA 0.00000e+00 3.00000e-13 0.00000e+00 -3.03572e+16
MIGRAD MINIMIZATION HAS CONVERGED.
FCN=1543.52 FROM MIGRAD STATUS=CONVERGED 3616 CALLS 3618 TOTAL
EDM=3.94501e-05 STRATEGY= 1 ERROR MATRIX UNCERTAINTY 0.9 per cent
EXT PARAMETER STEP FIRST
NO. NAME VALUE ERROR SIZE DERIVATIVE
1 slope pmtA - pmtB 1.59567e-01 1.22686e-03 1.49114e-05 -1.14719e+00
2 slope pmtA - pinAl 2.06255e+01 1.15214e-01 -1.41689e-03 -6.01425e-02
3 slope pmtA - pinAh 6.54140e+00 3.63697e-02 -3.15853e-04 -2.15254e-01
4 slope pmtB - pinAl 3.31382e+00 2.02621e-02 2.37405e-05 1.95499e-01
5 slope pmtB - pinAh 1.05126e+00 6.50788e-03 3.60976e-05 6.68045e-01
6 slope pmtB - pmtA 1.30295e-01 9.41983e-04 -6.33256e-06 -1.90133e+00
7 slope pmtB - pinBl 3.04320e+01 1.82908e-01 -4.34448e-04 5.07045e-02
8 slope pmtB - pinBh 1.25025e+01 7.33315e-02 3.96024e-05 1.10950e-01
9 slope pmtB - pinAl 4.01183e+00 2.01397e-02 -1.18064e-04 2.52390e-01
10 slope pmtA - pinAh 1.64528e+00 7.22481e-03 -1.12591e-05 -5.53290e-01
11 slope pinAl - pinAh 3.17243e-01 3.83980e-04 7.65941e-06 -3.14604e+02
12 slope pinBl - pinBh 4.10569e-01 5.59306e-04 2.43971e-06 -3.99833e+01
13 curvature pmtA -1.86194e-05 1.58982e-06 -1.80799e-08 3.87866e+04
14 curvature pmtB -3.18930e-05 1.56027e-06 1.46914e-09 -4.13775e+04
15 curvature pinAl -1.02195e-04 1.83665e-05 -3.74102e-08 9.81386e+04
16 curvature pinAh -3.97491e-05 5.87250e-06 -4.52470e-08 -3.05882e+05
17 curvature pinBl -6.23563e-04 1.85423e-05 3.90738e-08 1.07054e+04
18 curvature pinBh -2.41471e-04 6.00780e-06 3.75872e-09 -2.68463e+04
19 curvature pmtA 1.21934e-09 9.34996e-11 1.04315e-12 4.12731e+08
20 curvature pmtB 1.38705e-09 1.04923e-10 -1.52784e-13 -3.70123e+08
21 curvature pinAl -7.55580e-08 1.39041e-08 -1.69012e-11 9.35333e+07
22 curvature pinAh 4.03992e-09 1.27447e-09 1.27532e-11 -9.05513e+08
23 curvature pinBl 5.99605e-07 2.01802e-08 -6.82185e-11 5.71357e+06
24 curvature pinBh 6.48339e-08 2.40720e-09 -4.77370e-12 -3.94406e+07
25 curvature pmtA 8.44780e-11 4.38989e-12 6.02822e-14 9.19761e+10
EXTERNAL ERROR MATRIX. NDIM= 25 NPAR= 25 ERR DEF=1

4

Could you send the shortest possible running script reproducing this problem?

Rene

5

HI Rene
I have found the problem. I was calling TMinuit with maxpar=2
TMinuit *gMinuit = new TMinuit(2);
and then defining 28 parameters. This allowed up to 25 parameters and ignored more parameters. If I change the 2 to 28 it works, it does not need the
TVirtualFitter::Fitter(0,50);
My fault but the diagnostic was not very obvious…

Incidentally if I added
gMinuit->BuildArrays(28);
to the changed code that worked, it only fitted 18 parameters, the rest were left fixed.

My FCN is complicated and uses the MINOS database however if you want an example which looks like it does the same thing at the start of the program, I can send you one.

Thanks
Peter

6

The smily face in the previous note should be 28