Equation 9 · Part 1 · Comparing the Main Approaches to AI for Science and Medicine
Symbol N
What this part means
the number of atoms compared.
Its job in the formula
N is a part of this expression. Its role is fixed by the surrounding article and by the operations shown in the formula.
Full expression→Symbol N→Article meaning
Where the article explains it
where is the coordinate of atom i in the experimentally solved structure, is the corresponding coordinate in the predicted structure after optimal superposition of the two, and N is the number of atoms compared.
The passage around this formula
where is the coordinate of atom i in the experimentally solved structure, is the corresponding coordinate in the predicted structure after optimal superposition of the two, and N is the number of atoms compared. This is a statement about the average positional deviation of one predicted, static conformation from one experimentally solved, static conformation. It is not, by construction, a statement about how the molecule moves, how quickly it interconverts between conformations, or what its folding pathway looks like — and that distinction is the entire content of what comes next.
Learn the underlying idea
A variable is a named place for a value. Its letter is a local label: x can mean position in one formula and a data point in another.
Open the illustrated variables: a letter stands for a value guide →
See this notation across published equations →
Sources cited in the article section
- [9] Highly Accurate Protein Structure Prediction with AlphaFold ↗
- [11] Machine Learning for Molecular Simulation ↗
- [10] Sampling Alternative Conformational States of Transporters and Receptors with AlphaFold2 ↗
These citations provide research context; check each source for the exact claim it supports.