}
	index, err := p.SampleIndexByName(sampleIndex)
	if err != nil {
		return nil, nil, nil, err
	}
	value = valueExtractor(index)
	if mean {
		meanDiv = valueExtractor(0)
	}
	v = p.SampleType[index]
	return
}

func valueExtractor(ix int) sampleValueFunc {
	return func(v []int64) int64 {
		return v[ix]
	}
}