# DerivativesOrder

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#### DerivativesOrder

Section Mesh::Derivatives
Type integer
Default 4

This variable gives the discretization order for the approximation of the differential operators. This means, basically, that DerivativesOrder points are used in each positive/negative spatial direction, e.g. DerivativesOrder = 1 would give the well-known three-point formula in 1D. The number of points actually used for the Laplacian depends on the stencil used. Let $O$ = DerivativesOrder, and $d$ = Dimensions.

• stencil_star: $2 O d + 1$
• stencil_cube: $(2 O + 1)^d$
• stencil_starplus: $2 O d + 1 + n$ with n being 8 in 2D and 24 in 3D.

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