NoPricesInversionModel
                        Function to invert model, so amenities, wages,
                        productivities, and development density are
                        chosen to match model to data. This function
                        requires data on the amount of floorspace.
PricesInversionModel    Function to invert model, so amenities, wages,
                        productivities, and development density are
                        chosen to match model to data. In this version
                        you require housing prices
array_operator          Array operator to mimic
                        different-dimension-array element-wise
                        operations in MATLAB. It receives as input two
                        arrays of potentially different dimensions, it
                        resizes them to have same dimensions and
                        finally performs the element-wise operation.
av_income_simple        Computes average income in each location, which
                        is the weighted average of the income of the
                        people living in the location.
commuting_matrix        Function to transform travel times into iceberg
                        commuting costs
density_development     Computes residential and commercial floorspace
                        supply and equilibrium prices.
inversionModel          Function to invert model, so amenities, wages,
                        productivities, and development density are
                        chosen to match model to data.
living_amenities_simple
                        Function to estimate amenity parameters of
                        locations where users live.
productivity            Computes productivity levels in each location
solveModel              Function to solve counterfactuals.
sumDims                 Collapse array along one of the dimensions by
                        adding the elements along that dimension.
sumDims2                Collapse array 2 along one of the dimensions by
                        adding the elements along that dimension.
wages_inversion         Function to compute equilibrium wages that make
                        the model labor in every location in equal to
                        the observed data. It finds the w's such that
                        equation (3.2) holds.
