Presentation of Yves Boutelout during the ALATNET training course on Numerical Analysis in Kranjska Gora, 29-31 May 2002.

Schedule of the lectures :
– first: a "cultural" lecture with historical digression about variational calculus
– then an introduction to the optimal estimation theory,
– and to variational data assimilation in meteorology
– finally a lecture on the minimization algorithms