I’m dealing with the data of m31 using the HSC pipeline 8.5.3,when I process jointcal,using the command:

```
jointcal.py /data/HSC/ --calib /data/HSC/CALIB --rerun m31 --id visit=184620..184632:2 ccd=0..8^10..103
```

erros hapened:

```
jointcal WARN: ccdImage 184624_49 has only 78 measuredStars (desired 100)
jointcal WARN: ccdImage 184624_50 has only 84 measuredStars (desired 100)
jointcal WARN: ccdImage 184626_49 has only 84 measuredStars (desired 100)
jointcal WARN: ccdImage 184628_49 has only 85 measuredStars (desired 100)
jointcal WARN: ccdImage 184628_50 has only 84 measuredStars (desired 100)
jointcal WARN: ccdImage 184630_50 has only 77 measuredStars (desired 100)
jointcal WARN: ccdImage 184632_50 has only 88 measuredStars (desired 100)
jointcal WARN: still some outliers but chi2 increases - retry
jointcal.AstrometryFit INFO: assignIndices: Now fitting Distortions Positions
CHOLMOD warning: not positive definite
jointcal.AstrometryFit ERROR: minimize: factorization failed
jointcal INFO: Model chi2/ndof : 3.15378e+19/547524=5.76008e+13
jointcal WARN: ccdImage 184624_49 has only 78 measuredStars (desired 100)
jointcal WARN: ccdImage 184624_50 has only 84 measuredStars (desired 100)
jointcal WARN: ccdImage 184626_49 has only 84 measuredStars (desired 100)
jointcal WARN: ccdImage 184628_49 has only 85 measuredStars (desired 100)
jointcal WARN: ccdImage 184628_50 has only 84 measuredStars (desired 100)
jointcal WARN: ccdImage 184630_50 has only 77 measuredStars (desired 100)
jointcal WARN: ccdImage 184632_50 has only 88 measuredStars (desired 100)
jointcal FATAL: Failed processing tract 0, RuntimeError: Chi2 minimization failure, cannot complete fit.
```

And I modify the config

```
jointcal.py /data/HSC/ --calib /data/HSC/CALIB --rerun m31 --id visit=184620..184632:2 ccd=0..8^10..103 --config minMeasuredStarsPerCcd=70 --clobber-config
```

jointcal.py still cannot process

log :

```
jointcal.AstrometryFit WARN: Inconsistent measurement errors :drop measurement at x: 391.139 y: 1058.38 in image 184624_8
jointcal.AstrometryFit WARN: Inconsistent measurement errors :drop measurement at x: 1179.35 y: 2873.91 in image 184624_36
jointcal.AstrometryFit WARN: Inconsistent measurement errors :drop measurement at x: 148.654 y: 3063.83 in image 184624_36
jointcal.AstrometryFit WARN: Inconsistent measurement errors :drop measurement at x: 391.139 y: 1058.38 in image 184624_8
jointcal.AstrometryFit WARN: Inconsistent measurement errors :drop measurement at x: 1179.35 y: 2873.91 in image 184624_36
jointcal.AstrometryFit WARN: Inconsistent measurement errors :drop measurement at x: 148.654 y: 3063.83 in image 184624_36
jointcal.AstrometryFit INFO: findOutliers: found 7 meas outliers and 0 ref outliers
jointcal.AstrometryFit WARN: chi2 went up, skipping outlier rejection loop
jointcal.AstrometryFit INFO: Number of outliers (Measured + Reference = Total): 19 + 0 = 19
jointcal INFO: Model chi2/ndof : 2.94896e+19/547534=5.38589e+13
jointcal WARN: still some outliers but chi2 increases - retry
jointcal.AstrometryFit INFO: assignIndices: Now fitting Distortions Positions
jointcal.AstrometryFit WARN: Inconsistent measurement errors :drop measurement at x: 534.234 y: 2534.19 in image 184630_26
jointcal.AstrometryFit WARN: Inconsistent measurement errors :drop measurement at x: 534.234 y: 2534.19 in image 184630_26
jointcal.AstrometryFit INFO: findOutliers: found 2 meas outliers and 0 ref outliers
jointcal.AstrometryFit INFO: findOutliers: found 1 meas outliers and 0 ref outliers
jointcal.AstrometryFit INFO: findOutliers: found 2 meas outliers and 0 ref outliers
jointcal.AstrometryFit WARN: chi2 went up, skipping outlier rejection loop
jointcal.AstrometryFit INFO: Number of outliers (Measured + Reference = Total): 5 + 0 = 5
jointcal INFO: Model chi2/ndof : 3.15378e+19/547524=5.76008e+13
jointcal WARN: still some outliers but chi2 increases - retry
jointcal.AstrometryFit INFO: assignIndices: Now fitting Distortions Positions
CHOLMOD warning: not positive definite
jointcal.AstrometryFit ERROR: minimize: factorization failed
jointcal INFO: Model chi2/ndof : 3.15378e+19/547524=5.76008e+13
jointcal FATAL: Failed processing tract 0, RuntimeError: Chi2 minimization failure, cannot complete fit.
```

And I search on github, jointcal.py

The code is like that:

```
elif result == MinimizeResult.NonFinite:
filename = self._getDebugPath("{}_failure-nonfinite_chi2-{}.csv".format(name, dataName))
# TODO DM-12446: turn this into a "butler save" somehow.
fitter.saveChi2Contributions(filename+"{type}")
msg = "Nonfinite value in chi2 minimization, cannot complete fit. Dumped star tables to: {}"
raise FloatingPointError(msg.format(filename))
elif result == MinimizeResult.Failed:
raise RuntimeError("Chi2 minimization failure, cannot complete fit.")
```

So,what’s the true reasons that casued that?How should I handle that,Has anyone occued the same problems like that?

Thank you!