  We introduce and study nonlinear production - consumption equilibrium (NPCE).
The NPCE is a combination and generalization of both classical linear
programming (LP) and classical input-output (IO) models. In contrast to LP and
IO the NPCE has both production and consumption components. Moreover, the
production cost, the consumption and the factors (resources) availability are
not fixed. Instead they are corespondent functions of the production output,
prices of goods and prices of factors. At the NPCE the total production cost
reaches its minimum, while the total consumption, without factors expences,
reaches its maximum. At the same time the production cost is consistent with
the production output, the consumption is consistent with the prices for goods
and the factors availability is consistent with prices for factors. Finding
NPCE is equivalent to solving a variational inequality (VI) with a particular
nonlinear operator and a simple feasible set. Under natural assumptions on the
production, consumption and factor operators the NPCE exists and it is unique.
Projection on the feasible set {\Omega} is a low cost operation, therefore for
solving the VI we use two projection methods. Each of them requires at each
step few matrix by vector multiplications and allows, along with convergence
and convergence rate, establish complexity bound. The methods decompose the
problem, so both the primal and the dual variables are computed simultaneously.
On the other hand, both methods are pricing mechanisms for establishing NPCE,
which is a generalization of Walras - Wald equilibrium (see [12]) in few
directions.
