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Third flattening of ellipse from eccentricity

Support for nonscalar input, including the syntax n = ecc2n(ellipsoid), will be removed in a future release.


n = ecc2n(ecc)
n = ecc2n(ellipsoid)


n = ecc2n(ecc) computes the parameter n (the "third flattening") of an ellipse (or ellipsoid of revolution) given its eccentricity ecc. n is defined as (a-b)/(a+b), where a is the semimajor axis and b is the semiminor axis. Except when the input has 2 columns (or is a row vector), each element is assumed to be an eccentricity and the output n has the same size as ecc.

n = ecc2n(ellipsoid), where ellipsoid has two columns (or is a row vector), assumes that the eccentricity is in the second column, and a column vector is returned.

Introduced before R2006a