The opts arguments may contain one or more of the options below.

fullset = boolean. In the case of the function call LeadingDerivative(ideal), applies the function also over the differential polynomials which state that the derivatives of the parameters are zero. Default value is false. This option is incompatible with the diff notation.

notation = jet, tjet, diff or Diff. Specifies the notation used for the result of the function call. If not specified, the notation of the first argument is used.

memout = nonnegative. Specifies a memory limit, in MB, for the computation. Default is zero (no memory out).

The function call LeadingDerivative(p,R) returns the leading derivative of p with respect to the ranking of R or the one of its embedding polynomial ring if R is an ideal. The polynomial p is assumed to be non-numeric. It may, however, only depend on independent variables. In this case, the leading independent variable is returned.

The function call LeadingDerivative(L,R) returns the list or the set of the leading derivatives of the elements of L with respect to the ranking of R.

If ideal is a regular differential chain, the function call LeadingDerivative(ideal) returns the list of the leading derivatives of the chain elements. If ideal is a list of regular differential chains, the function call LeadingDerivative(ideal) returns a list of lists of leading derivatives.

This command is part of the DifferentialAlgebra:-Tools package. It can be called using the form LeadingDerivative(...) after executing the command with(DifferentialAlgebra:-Tools). It can also be directly called using the form DifferentialAlgebra[Tools][LeadingDerivative](...).

$\mathrm{with}\left(\mathrm{DifferentialAlgebra}\right)\:$$\mathrm{with}\left(\mathrm{Tools}\right)\:$

$R≔\mathrm{DifferentialRing}\left(\mathrm{derivations}=\left[x\,y\right]\,\mathrm{blocks}=\left[\left[v\,u\right]\,p\right]\,\mathrm{parameters}=\left[p\right]\right)$

$R≔\mathrm{differential\_ring}$

$\mathrm{LeadingDerivative}\left(u\left[x,y\right]v\left[y\right]-u+p\,R\right)$

$u_{x,y}$

$\mathrm{ideal}≔\mathrm{RosenfeldGroebner}\left(\left[{u\left[x\right]}^2-4u\,u\left[x,y\right]v\left[y\right]-u+p\,v\left[x,x\right]-u\left[x\right]\right]\,R\right)$

$\mathrm{ideal}≔\left[\mathrm{regular\_differential\_chain}\,\mathrm{regular\_differential\_chain}\right]$

$\mathrm{Equations}\left(\mathrm{ideal}\left[1\right]\right)$

$\left[v_{x,x}-u_x\,p{u}_x{u}_y-u{u}_x{u}_y+4u{v}_y\,u_x^2-4u\,u_y^2-2u\right]$

$\mathrm{LeadingDerivative}\left(\mathrm{ideal}\left[1\right]\right)$

$\left[v_{x,x}\,v_y\,u_x\,u_y\right]$