|  |  D.15.12.34 derivationToString Procedure from librarydifform.lib(see  difform_lib).
 
Example:Usage:
derivationToString(phi,#); phi derivation, # list
Return:
the derivation as a string, describing the image of the degree-1 generators,
optionally ordered by a given monomial ordering on the generators
Remarks:
To sort the images of the generators in the output string, difformListSort is used.
Note:
to define an ordering for the generators, one can use:
- #[1] = 'gen'
 - #[2]: a monomial ordering as string
 - #[3]: an optional weight vector
 the standard ordering is the ordering of the differential algebra
 
 See also:
 derivationPrint;
 difformGenToString;
 difformListSort.|  | LIB "difform.lib";
ring R = 0,(x,y,z),dp;
diffAlgebra();
==> // The differential algebra Omega_R was constructed and the differential \
   forms dDx, dDy, dDz, dx, dy, dz are available.
list L; L[1] = list(dx,dy,dz); L[2] = list(x2,y-23xz,xz4);
derivation phi = L;
///////////////////////////////////
// String with standard ordering //
///////////////////////////////////
print(derivationToString(phi));
==>  Omega_R^1 --> R
==>        dz |--> xz4
==>        dy |--> -23xz+y
==>        dx |--> x2
==> 
//////////////////////////////////
// String with changed ordering //
//////////////////////////////////
print(derivationToString(phi,"gen","wp",intvec(-1,-1,1)));
==>  Omega_R^1 --> R
==>        dy |--> -23xz+y
==>        dx |--> x2
==>        dz |--> xz4
==> 
kill Omega_R,dx,dy,dz,L,phi;
 | 
 
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