docstr: Returns the row principal coordinates.
docstr_tok: ["Returns","the","row","principal","coordinates","."]
code: def row_coordinates(self, X):
      """Returns the row principal coordinates."""
  
      if (X.index != self.row_contributions_.index).any():
          raise NotImplementedError(
              "Supplementary rows are not supported yet"
          )
  
      X = (X - X.mean()) / ((X - X.mean()) ** 2).sum() ** 0.5
      Z = pd.concat(
          (
              X[cols] / self[g].eigenvalues_[0] ** 0.5
              for g, cols in self.groups_.items()
          ),
          axis="columns",
      )
      U = self.svd_.U
      s = self.svd_.s
      M = np.full(len(X), 1 / len(X))
  
      return (Z @ Z.T) @ (M[:, np.newaxis] ** (-0.5) * U * s**-1)
  
imports: from __future__ import annotations
  import collections
  import altair
  import numpy
  import pandas
  import sklearn.utils
  from prince import pca, utils
label_desc: Use image node_id 6 for calling the MFA obj's underlying member method code with example usage: obj.row_coordinates(X) and returns: unknown