**X** es la matriz centrada (**X** is the centered matrix).

**Xcov** es la matriz de covarianzas de X *(Xcov is the covariance matrix of X).*

Con la función **“eigen”** calculamos los “eigenvectors” y “eigenvalues” de Xcov*.(With the function ***“eigen”** we calculate the “eigenvectors” and “eigenvalues” of **Xcov**).

Para hacer todo al mismo tiempo, podemos usar la función “prcomp”.*(**To do everything at the same time we can use the function “prcomp”).*

La diferencia es que con **eigen** obtenemos la varianza y con **prcomp** las desviaciones estándar.

*The diference is that with ***eigen** we get the variances, and with **prcomp** the standard deviations.

Podemos comprobar estos resultados con el cálculo del fichero PCA de la entrada anterior.

*We can compare this results with the PCA file got in Win ISI in the previous post.*

*Related*

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