feat: Running CNs added to SiteRDF

[Danbr4d]

Added into SiteRDF the functionality to calculate the running coordination number for a configuration

[trisyoungs]

Close! The ultimate result at the maximum of the distanceRange_ is indeed the integral of the whole histogram, and every bin up to that point is the sum of all those before it. So what you can do here is create your sumRunNHist histogram (and maybe rename to runningCNHist or similar) using the same distanceRange_ as histAB.

Then, you can simply step over the bins in each with a zip and keep track of the running bin total from histAB as you go, adding those total values at each bin into your new histogram. Note that we should do this for the raw (i.e. instantaneous, just calculated) bins of histAB so that we can form an average.

[trisyoungs]

Careful - distanceRange_.x is just the minimum value of the distance range to use. In fact, you don't need to initialise this class at all, since that will happen automatically on the first addition (+=) to it later on.

Suggested change

dataRunningCN.initialise(distanceRange_.x);

[trisyoungs]

In fact, we can do all of this summation in a std::transform...

Suggested change

	std::vector<double> runningCN;
	// Zip over all distanceRange and calculate running CN
	double countCN{};
	for (const auto &&[x, currentCN] : zip(histAB.binCentres(), histAB.data().values()))
	{
	runningCN[x] += currentCN;
	}
	// Add data into SampledData1D
	dataRunningCN += runningCN;

[trisyoungs]

Here we go. So we have the normalised bin data in instBinValues, and we can convert that into the running coordination numbers in-place by doing this nice std::transform. Essentially we just step over each value and calculate and return a replacement value which is the running coordination number (which we keep track of the in the sum variable):

Suggested change

	auto sum = 0.0;
	std::transform(instBinValues.values().begin(), instBinValues.values().end(), instBinValues.values().begin(), [&](const auto &currentBin) {sum += currentBin; return sum; } );