add.ellipse: Add ellipse to an existing plot
In netresponse: Functional Network Analysis

Calculates and plots ellipse corresponding to specified confidence interval in 2-dimensional plot

add.ellipse(
  centroid,
  covmat,
  confidence = 0.95,
  npoints = 100,
  col = "black",
  ...
)

`centroid`	Vector with two elements defining the ellipse centroid.
`covmat`	Covariance matrix for the investigated data. Only diagonal covariances supported.
`confidence`	Confidence level determining the ellipse borders based on the covariance matrix.
`npoints`	Number of plotting points.
`col`	Color.
`...`	Other arguments to be passed.