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- Tue Feb 10 12:27:18 2004 run on Linux
- %*******************************************************************%
- % %
- % C O N L A W . T S T %
- % ------------------- %
- % conlaw.tst contains test examples for the programs conlaw0.red %
- % conlaw1.red, conlaw2.red, conlaw3.red, conlaw4.red. To run %
- % this test read in the files crack.red, conlaw0.red, conlaw1.red, %
- % conlaw2.red, conlaw3.red, conlaw4.red or load their compiled %
- % version before. %
- % %
- % Author: Thomas Wolf %
- % Date: 15. June 1999, 6. May 2003 %
- % %
- % Details about the syntax of conlaw1-4 are given in conlaw.tex. %
- % To run this file read in or load crack, conlaw0 before. %
- % %
- % The statement lisp(print_:=nil); suppresses output of the %
- % computation. To see details of it do lisp(print_:=50). %
- % %
- %*******************************************************************%
- load crack ;
- % ,conlaw0,conlaw1,conlaw2,conlaw3,conlaw4$
- lisp(depl!*:=nil)$
- % clearing of all dependencies
- setcrackflags()$
- % standart flags
- lisp(print_:=nil)$
- % no output of the calculation
- %% off batch_mode$
- comment -------------------------------------------------------------
- The following example calculates all conservation laws of the KdV-
- equation with a characteristic function of order not higher than two;
- nodepnd {u}$
- % deletes all dependencies of u
- depend u,x,t$
- % declares u to be a function of x,t
- conlaw4({{df(u,t) = u*df(u,x)+df(u,x,3)}, {u}, {t,x}},
- {0, 2, t, {}, {}} )$
- --------------------------------------------------------------------------
- This is CONLAW4 - a program for calculating conservation laws of DEs
- The DE under investigation is :
- u =u + u *u
- t 3x x
- for the function(s): u(t,x)
- ======================================================
- Currently conservation laws with characteristic
- function(s) of order 0 are determined
- ======================================================
- Conservation law:
- ( u ) * ( u - u - u *u )
- t 3x x
- =
- 1 2
- df( ---*u , t )
- 2
- +
- 1 2 1 3
- df( - u *u + ---*u - ---*u , x )
- 2x 2 x 3
- ======================================================
- Conservation law:
- ( t*u + x ) * ( u - u - u *u )
- t 3x x
- =
- 1 2
- df( ---*t*u + u*x, t )
- 2
- +
- 1 2 1 3 1 2
- df( - u *t*u - u *x + ---*u *t + u - ---*t*u - ---*u *x, x )
- 2x 2x 2 x x 3 2
- ======================================================
- Conservation law:
- ( 1 ) * ( u - u - u *u )
- t 3x x
- =
- df( u, t )
- +
- 1 2
- df( - u - ---*u , x )
- 2x 2
- ======================================================
- Currently conservation laws with characteristic
- function(s) of order 1 are determined
- ======================================================
- There is no conservation law of this order.
- ======================================================
- Currently conservation laws with characteristic
- function(s) of order 2 are determined
- ======================================================
- Conservation law:
- 2
- ( - 2*u - u ) * ( u - u - u *u )
- 2x t 3x x
- =
- 2 1 3
- df( u - ---*u , t )
- x 3
- +
- 2 2 1 4
- df( - 2*u *u + u + u *u + ---*u , x )
- t x 2x 2x 4
- ======================================================
- 2
- {{{ - 2*df(u,x,2) - u },
- 2 3
- 3*df(u,x) - u
- {-----------------,
- 3
- 2 2 4
- - 8*df(u,t)*df(u,x) + 4*df(u,x,2) + 4*df(u,x,2)*u + u
- -----------------------------------------------------------}},
- 4
- 2
- - 2*df(u,x,2) - u
- {{1},{u,---------------------}},
- 2
- {{t*u + x},
- u*(t*u + 2*x)
- {---------------,
- 2
- 2 3
- ( - 6*df(u,x,2)*t*u - 6*df(u,x,2)*x + 3*df(u,x) *t + 6*df(u,x) - 2*t*u
- 2
- - 3*u *x)/6}},
- {{u},
- 2 2 3
- u - 6*df(u,x,2)*u + 3*df(u,x) - 2*u
- {----,--------------------------------------}}}
- 2 6
- comment -------------------------------------------------------------
- The next example demonstrates that one can specify an ansatz
- for the characteristic function of one or more equations of the
- PDE-system. In this example all conservation laws of the wave
- equation which is written as a first order system are calculated
- such that the characteristic functions of the first of both
- equations is proportional to df(u,x,2). (This will include zero
- as it is a multiple of df(u,x,2) too.)
- In the following input the equations are solved for the t-derivatives,
- so the t-derivatives will be substituted in the conservation-law-
- conditions, so the ansatz for q_1 should have no t-derivatives of u
- included. Therefore the function r in q_1 below is specified as
- depending on t,x,u,v,df(u,x),df(v,x).
- In the call of conlaw2 the list of variables is {t,x} and x is
- the second of the variables (could equally well be in reverse order).
- Therefore df(u,x) takes the form u!`2 when the dependencies of r
- are specified (see conlaw.tex);
- nodepnd {u,v,r}$
- depend u,x,t$
- depend v,x,t$
- depend r,t,x,u,v,u!`2,v!`2$
- q_1:=r*df(u,x,2)$
- conlaw2({{df(u,t)=df(v,x),
- df(v,t)=df(u,x) }, {u,v}, {t,x}},
- {2, 2, t, {r}, {}})$
- --------------------------------------------------------------------------
- This is CONLAW2 - a program for calculating conservation laws of DEs
- The DEs under investigation are :
- u =v
- t x
- v =u
- t x
- for the function(s): u(x,t), v(x,t)
- ======================================================
- A special ansatz of order 2 for the characteristic
- function(s) is investigated.
- Conservation law:
- ( u ) * ( u - v )
- 2x t x
- +
- ( v ) * ( - u + v )
- 2x x t
- =
- 1 2 1 2
- df( - ---*u - ---*v , t )
- 2 x 2 x
- +
- df( u *u - u *v + v *v , x )
- t x x x t x
- ======================================================
- {{{df(u,x,2),df(v,x,2)},
- 2 2
- - (df(u,x) + df(v,x) )
- {--------------------------,
- 2
- df(u,t)*df(u,x) - df(u,x)*df(v,x) + df(v,t)*df(v,x)}}}
- clear q_1$
- nodepnd {q_1}$
- comment -------------------------------------------------------------
- For the Burgers equation the following example finds all conservation
- laws of zero'th order in the characteristic function up to the solution
- of the linear heat equation. This is an example for what happens when
- not all conditions could be solved, but it is also an example which
- shows that not only characteristic functions of polynomial or rational
- form can be found;
- nodepnd {u}$
- depend u,x,t$
- conlaw1({{df(u,t)=df(u,x,2)+df(u,x)**2/2}, {u}, {t,x}},
- {0, 0, t, {}, {}} )$
- --------------------------------------------------------------------------
- This is CONLAW1 - a program for calculating conservation laws of DEs
- The DE under investigation is :
- 1 2
- u =u + ---*u
- t 2x 2 x
- for the function(s): u(x,t)
- ======================================================
- Currently conservation laws with a conserved density
- of order 0 are determined
- ======================================================
- The function c_66(x,t) is not constant!
- There are remaining conditions: {c_66 + c_66 }
- t 2x
- for the functions: c_66(x,t)
- Corresponding CLs might not be shown below as they
- could be of too low order.
- ======================================================
- Conservation law:
- u/2 1 2
- ( e *c_66 ) * ( u - u - ---*u )
- t 2x 2 x
- =
- u/2
- df( 2*e *c_66, t )
- +
- u/2 u/2
- df( 2*e *c_66 - e *u *c_66, x )
- x x
- An attempt to factor out linear differential operators:
- 1 2
- eq_1:=u - u - ---*u
- t 2x 2 x
- u/2
- l_1:=e
- u/2
- e *eq_1 = 2*(l_1 - l_1 )
- t 2x
- ======================================================
- u/2
- {{{e *c_66},
- u/2
- {2*e *c_66,
- u/2
- e *(2*df(c_66,x) - df(u,x)*c_66)}}}
-
- comment -------------------------------------------------------------
- In this example all conservation laws of the Ito system are calculated
- that have a conserved density of order not higher than one.
- This is a further example of non-polynomial conservation laws;
- nodepnd {u,v}$
- depend u,x,t$
- depend v,x,t$
- conlaw1({{df(u,t)=df(u,x,3)+6*u*df(u,x)+2*v*df(v,x),
- df(v,t)=2*df(u,x)*v+2*u*df(v,x) }, {u,v}, {t,x}},
- {0, 1, t, {}, {}})$
- --------------------------------------------------------------------------
- This is CONLAW1 - a program for calculating conservation laws of DEs
- The DEs under investigation are :
- u =u + 6*u *u + 2*v *v
- t 3x x x
- v =2*u *v + 2*v *u
- t x x
- for the function(s): u(x,t), v(x,t)
- ======================================================
- Currently conservation laws with a conserved density
- of order 0 are determined
- ======================================================
- Conservation law:
- ( -1 ) * ( - 2*u *v + v - 2*v *u )
- x t x
- +
- ( 0 ) * ( u - u - 6*u *u - 2*v *v )
- t 3x x x
- =
- df( - v, t )
- +
- df( 2*u*v, x )
- ======================================================
- Conservation law:
- ( 2*v ) * ( - 2*u *v + v - 2*v *u )
- x t x
- +
- ( 2*u ) * ( u - u - 6*u *u - 2*v *v )
- t 3x x x
- =
- 2 2
- df( u + v , t )
- +
- 2 3 2
- df( - 2*u *u + u - 4*u - 4*u*v , x )
- 2x x
- ======================================================
- Conservation law:
- ( 0 ) * ( - 2*u *v + v - 2*v *u )
- x t x
- +
- ( 1 ) * ( u - u - 6*u *u - 2*v *v )
- t 3x x x
- =
- df( u, t )
- +
- 2 2
- df( - u - 3*u - v , x )
- 2x
- ======================================================
- Currently conservation laws with a conserved density
- of order 1 are determined
- ======================================================
- Conservation law:
- ( - 2*v ) * ( - 2*u *v + v - 2*v *u )
- x t x
- +
- ( - 2*u ) * ( u - u - 6*u *u - 2*v *v )
- t 3x x x
- =
- 2 2
- df( - u - v , t )
- +
- 2 3 2
- df( 2*u *u - u + 4*u + 4*u*v , x )
- 2x x
- ======================================================
- Conservation law:
- ( - 4*u*v ) * ( - 2*u *v + v - 2*v *u )
- x t x
- +
- 2 2
- ( - 2*u - 6*u - 2*v ) * ( u - u - 6*u *u - 2*v *v )
- 2x t 3x x x
- =
- 2 3 2
- df( u - 2*u - 2*u*v , t )
- x
- +
- 2 2 2 4 2 2 4
- df( - 2*u *u + u + 6*u *u + 2*u *v + 9*u + 10*u *v + v , x )
- t x 2x 2x 2x
- ======================================================
- Conservation law:
- 2 2
- 2*v *v - 3*v - 4*u*v
- 2x x
- ( -------------------------- ) * ( - 2*u *v + v - 2*v *u )
- 4 x t x
- v
- +
- 4
- ( --- ) * ( u - u - 6*u *u - 2*v *v )
- v t 3x x x
- =
- 2 2
- - v + 4*u*v
- x
- df( -----------------, t )
- 3
- v
- +
- 2 2 2 2 4
- - 4*u *v - 4*u *v *v + 2*v *v - 2*v *u - 8*u *v - 8*v
- 2x x x t x x
- df( --------------------------------------------------------------, x )
- 3
- v
- ======================================================
- 2 2
- 2*df(v,x,2)*v - 3*df(v,x) - 4*u*v 4
- {{{-------------------------------------,---},
- 4 v
- v
- 2 2
- - df(v,x) + 4*u*v
- {----------------------,
- 3
- v
- 2 2
- (2*( - 2*df(u,x,2)*v - 2*df(u,x)*df(v,x)*v + df(v,t)*df(v,x) - df(v,x) *u
- 2 2 4 3
- - 4*u *v - 4*v ))/v }},
- 2 2
- {{ - 4*u*v,2*( - df(u,x,2) - 3*u - v )},
- 2 3 2
- {df(u,x) - 2*u - 2*u*v ,
- 2 2 2 4
- - 2*df(u,t)*df(u,x) + df(u,x,2) + 6*df(u,x,2)*u + 2*df(u,x,2)*v + 9*u
- 2 2 4
- + 10*u *v + v }},
- {{ - 2*v, - 2*u},
- 2 2
- { - (u + v ),
- 2 3 2
- 2*df(u,x,2)*u - df(u,x) + 4*u + 4*u*v }},
- 2 2
- {{0,1},{u, - df(u,x,2) - 3*u - v }},
- {{2*v,2*u},
- 2 2
- {u + v ,
- 2 3 2
- - 2*df(u,x,2)*u + df(u,x) - 4*u - 4*u*v }},
- {{-1,0},{ - v,2*u*v}}}
- comment -------------------------------------------------------------
- In the next example the 5th order Korteweg - de Vries equation is
- investigated concerning conservation laws of order 0 and 1 in the
- conserved density P_t. Parameters a,b,c in the PDE are determined
- such that conservation laws exist. This complicates the problem by
- making it non-linear with a number of cases to be considered.
- Some of the subcases below can be combined to reduce their number
- which currently is not done automatically;
- nodepnd {u}$
- depend u,x,t$
- conlaw1({{df(u,t)=-df(u,x,5)-a*u**2*df(u,x)
- -b*df(u,x)*df(u,x,2)-c*u*df(u,x,3)},
- {u}, {t,x}},
- {0, 1, t, {a,b,c}, {}})$
- --------------------------------------------------------------------------
- This is CONLAW1 - a program for calculating conservation laws of DEs
- The DE under investigation is :
- 2
- u = - u - u *c*u - u *u *b - u *a*u
- t 5x 3x 2x x x
- for the function(s): u(x,t)
- ======================================================
- Currently conservation laws with a conserved density
- of order 0 are determined
- ======================================================
- The function c_232(x,t) is not constant!
- The function c_236(t) is not constant!
- There are remaining conditions: {c_232 + c_232 - c_236}
- t 5x
- for the functions: c_236(t), c_232(x,t)
- Corresponding CLs might not be shown below as they
- could be of too low order.
- ======================================================
- Conservation law:
- c=0,
- b=0,
- a=0,
- ( - c_232 ) * ( u + u )
- x t 5x
- =
- df( - c_232 *u, t )
- x
- +
- df( c_232 *u + c_232 *u - c_232 *u + c_232 *u - c_232 *u + c_236*u, x
- t 4x x 3x 2x 2x 3x x 4x
- )
- ======================================================
- Conservation law:
- a=0,
- b=3*c,
- ( 1 ) * ( u + u + u *c*u + 3*u *u *c )
- t 5x 3x 2x x
- =
- df( u, t )
- +
- 2
- df( u + u *c*u + u *c, x )
- 4x 2x x
- ======================================================
- Conservation law:
- a=0,
- b=3*c,
- ( - x ) * ( u + u + u *c*u + 3*u *u *c )
- t 5x 3x 2x x
- =
- df( - u*x, t )
- +
- 2
- df( - u *x + u - u *c*u*x - u *c*x + u *c*u, x )
- 4x 3x 2x x x
- ======================================================
- Conservation law:
- a=0,
- b=3*c,
- 2
- x
- ( ---- ) * ( u + u + u *c*u + 3*u *u *c )
- c t 5x 3x 2x x
- =
- 2
- u*x
- df( ------, t )
- c
- +
- 2 2 2 2 2
- u *x - 2*u *x + u *c*u*x + 2*u + u *c*x - 2*u *c*u*x + c*u
- 4x 3x 2x 2x x x
- df( ----------------------------------------------------------------------, x )
- c
- ======================================================
- Conservation law:
- 2
- ( -6 ) * ( u + u + u *c*u + u *u *b + u *a*u )
- t 5x 3x 2x x x
- =
- df( - 6*u, t )
- +
- 2 2 3
- df( - 6*u - 6*u *c*u - 3*u *b + 3*u *c - 2*a*u , x )
- 4x 2x x x
- ======================================================
- Conservation law:
- b=2*c,
- 2
- ( - 4*u ) * ( u + u + u *c*u + 2*u *u *c + u *a*u )
- t 5x 3x 2x x x
- =
- 2
- df( - 2*u , t )
- +
- 2 2 4
- df( - 4*u *u + 4*u *u - 2*u - 4*u *c*u - a*u , x )
- 4x 3x x 2x 2x
- ======================================================
- Conservation law:
- b=2*c,
- 2
- ( -6 ) * ( u + u + u *c*u + 2*u *u *c + u *a*u )
- t 5x 3x 2x x x
- =
- df( - 6*u, t )
- +
- 2 3
- df( - 6*u - 6*u *c*u - 3*u *c - 2*a*u , x )
- 4x 2x x
- ======================================================
- The function c_254(x,t) is not constant!
- The function c_259(t) is not constant!
- There are remaining conditions: {c_254 + c_254 + c_259}
- t 5x
- for the functions: c_259(t), c_254(x,t)
- Corresponding CLs might not be shown below as they
- could be of too low order.
- ======================================================
- Conservation law:
- c=0,
- b=0,
- a=0,
- ( - 2*u ) * ( u + u )
- t 5x
- =
- 2
- df( - u , t )
- +
- 2
- df( - 2*u *u + 2*u *u - u , x )
- 4x 3x x 2x
- ======================================================
- Conservation law:
- c=0,
- b=0,
- a=0,
- ( - c_254 ) * ( u + u )
- x t 5x
- =
- df( - c_254 *u, t )
- x
- +
- df( c_254 *u + c_254 *u - c_254 *u + c_254 *u - c_254 *u + c_259*u, x
- t 4x x 3x 2x 2x 3x x 4x
- )
- ======================================================
- Conservation law:
- b=0,
- c=0,
- - 3 2
- ( ------ ) * ( u + u + u *a*u )
- a t 5x x
- =
- - 3*u
- df( --------, t )
- a
- +
- 3
- - 3*u - a*u
- 4x
- df( -----------------, x )
- a
- ======================================================
- Conservation law:
- b=0,
- c=0,
- 2
- ( - 4*u ) * ( u + u + u *a*u )
- t 5x x
- =
- 2
- df( - 2*u , t )
- +
- 2 4
- df( - 4*u *u + 4*u *u - 2*u - a*u , x )
- 4x 3x x 2x
- ======================================================
- Currently conservation laws with a conserved density
- of order 1 are determined
- ======================================================
- Conservation law:
- b=0,
- c=0,
- - 4*u 2
- ( -------- ) * ( u + u + u *a*u )
- a t 5x x
- =
- 2
- - 2*u
- df( ---------, t )
- a
- +
- 2 4
- - 4*u *u + 4*u *u - 2*u - a*u
- 4x 3x x 2x
- df( ---------------------------------------, x )
- a
- ======================================================
- Conservation law:
- b=3*c,
- 3 2
- ( ---- ) * ( u + u + u *c*u + 3*u *u *c + u *a*u )
- 2 t 5x 3x 2x x x
- a
- =
- 3*u
- df( -----, t )
- 2
- a
- +
- 2 3
- 3*u + 3*u *c*u + 3*u *c + a*u
- 4x 2x x
- df( ------------------------------------, x )
- 2
- a
- ======================================================
- The function c_294(x,t) is not constant!
- The function c_303(x) is not constant!
- There are remaining conditions: {c_294 + c_294 + c_303 }
- t 5x 4x
- for the functions: c_303(x), c_294(x,t)
- Corresponding CLs might not be shown below as they
- could be of too low order.
- ======================================================
- Conservation law:
- c=0,
- b=0,
- a=0,
- ( 2*u ) * ( u + u )
- t 5x
- =
- 2
- df( u , t )
- +
- 2
- df( 2*u *u - 2*u *u + u , x )
- 4x 3x x 2x
- ======================================================
- Conservation law:
- c=0,
- b=0,
- a=0,
- ( - 2*u ) * ( u + u )
- 2x t 5x
- =
- 2
- df( u , t )
- x
- +
- 2 2 2 2
- df( - 2*u *u - 2*u *u + u - 2*u *u *c*u - 2*u *u *b - 2*u *a*u , x )
- t x 4x 2x 3x 3x x 2x x x
- ======================================================
- Conservation law:
- c=0,
- b=0,
- a=0,
- ( - c_294 + c_303 ) * ( u + u )
- x t 5x
- =
- df( - c_294 *u + c_303*u, t )
- x
- +
- df( c_294 *u + c_294 *u - c_294 *u + c_294 *u - c_294 *u - c_303 *u
- t 4x x 3x 2x 2x 3x x 4x 3x x
- + c_303 *u - c_303 *u + u *c_303 - u *c*c_294*u - u *u *b*c_294
- 2x 2x x 3x 4x 3x 2x x
- 2
- - u *a*c_294*u , x )
- x
- An attempt to factor out linear differential operators:
- eq_1:=u + u
- t 5x
- l_1:=u
- x
- l_2:= - u
- l_3:=u + u
- t,x 6x
- eq_1 = l_3
- x
- eq_1 = l_1 - l_2
- 4x t
- ======================================================
- Conservation law:
- a=0,
- b=3*c,
- ( 1 ) * ( u + u + u *c*u + 3*u *u *c )
- t 5x 3x 2x x
- =
- df( u, t )
- +
- 2
- df( u + u *c*u + u *c, x )
- 4x 2x x
- ======================================================
- Conservation law:
- a=0,
- b=3*c,
- ( x ) * ( u + u + u *c*u + 3*u *u *c )
- t 5x 3x 2x x
- =
- df( u*x, t )
- +
- 2
- df( u *x - u + u *c*u*x + u *c*x - u *c*u, x )
- 4x 3x 2x x x
- ======================================================
- Conservation law:
- a=0,
- b=3*c,
- 2
- - x
- ( ------- ) * ( u + u + u *c*u + 3*u *u *c )
- c t 5x 3x 2x x
- =
- 2
- - u*x
- df( ---------, t )
- c
- +
- 2 2 2 2 2
- - u *x + 2*u *x - u *c*u*x - 2*u - u *c*x + 2*u *c*u*x - c*u
- 4x 3x 2x 2x x x
- df( -------------------------------------------------------------------------, x
- c
- )
- ======================================================
- Conservation law:
- a=0,
- b=3*c,
- 2
- ( - 6*u - 3*c*u ) * ( u + u + u *c*u + 3*u *u *c )
- 2x t 5x 3x 2x x
- =
- 2 3
- df( 3*u - c*u , t )
- x
- +
- 2 2 2
- df( - 6*u *u - 6*u *u - 3*u *c*u + 3*u + 6*u *u *c*u - 6*u *c*u
- t x 4x 2x 4x 3x 3x x 2x
- 2 2 2 3 2 2
- - 6*u *u *b + 12*u *u *c - 3*u *c *u - 6*u *a*u , x )
- 2x x 2x x 2x x
- ======================================================
- Conservation law:
- 3 2
- a=----*c ,
- 10
- b=2*c,
- 3 2 2
- ( -100 ) * ( u + u + u *c*u + 2*u *u *c + ----*u *c *u )
- t 5x 3x 2x x 10 x
- =
- df( - 100*u, t )
- +
- 2 2 3 2
- df( - 100*u + 30*u *u *b*c *t*u - 100*u *u *b*x - 60*u *u *c *t*u
- 4x 2x x 2x x 2x x
- 2 2 4 2
- + 200*u *u *c*x - 100*u *c*u - 50*u *c + 30*u *a*c *t*u - 100*u *a*u *x
- 2x x 2x x x x
- 4 4 2 2 2 3
- - 9*u *c *t*u + 30*u *c *u *x - 10*c *u , x )
- x x
- ======================================================
- Conservation law:
- 3 2
- a=----*c ,
- 10
- b=2*c,
- 3 2 2
- ( - 100*u ) * ( u + u + u *c*u + 2*u *u *c + ----*u *c *u )
- t 5x 3x 2x x 10 x
- =
- 2
- df( - 50*u , t )
- +
- 2 2 3
- df( - 100*u *u + 100*u *u - 50*u + 30*u *u *b*c *t*u - 100*u *u *b*u*x
- 4x 3x x 2x 2x x 2x x
- 3 3 2 2 5
- - 60*u *u *c *t*u + 200*u *u *c*u*x - 100*u *c*u + 30*u *a*c *t*u
- 2x x 2x x 2x x
- 3 4 5 2 3 15 2 4
- - 100*u *a*u *x - 9*u *c *t*u + 30*u *c *u *x - ----*c *u , x )
- x x x 2
- ======================================================
- Conservation law:
- 3 2
- a=----*c ,
- 10
- b=2*c,
- 2 3 2 2
- ( - 1000*u - 300*c*u ) * ( u + u + u *c*u + 2*u *u *c + ----*u *c *u )
- 2x t 5x 3x 2x x 10 x
- =
- 2 3
- df( 500*u - 100*c*u , t )
- x
- +
- 2 2
- df( - 1000*u *u - 1000*u *u - 300*u *c*u + 500*u + 600*u *u *c*u
- t x 4x 2x 4x 3x 3x x
- 2 2 2 3 4
- - 800*u *c*u - 1000*u *u *b + 1400*u *u *c + 90*u *u *b*c *t*u
- 2x 2x x 2x x 2x x
- 2 4 4 2 2 2 3
- - 300*u *u *b*c*u *x - 180*u *u *c *t*u + 600*u *u *c *u *x - 300*u *c *u
- 2x x 2x x 2x x 2x
- 2 2 2 2 2 3 6 4
- - 1000*u *a*u + 300*u *c *u + 90*u *a*c *t*u - 300*u *a*c*u *x
- x x x x
- 5 6 3 4 3 5
- - 27*u *c *t*u + 90*u *c *u *x - 18*c *u , x )
- x x
- ======================================================
- Conservation law:
- 3 2
- a=----*c ,
- 10
- b=2*c,
- 2 2
- - 2000*u *c*t - 600*c *t*u + 2000*x
- 2x
- ( ---------------------------------------- ) * ( u + u + u *c*u + 2*u *u *c
- c t 5x 3x 2x x
- 3 2 2
- + ----*u *c *u )
- 10 x
- =
- 2 2 3
- 1000*u *c*t - 200*c *t*u + 2000*u*x
- x
- df( ---------------------------------------, t )
- c
- +
- 2 2
- df( ( - 2000*u *u *c*t - 2000*u *u *c*t - 600*u *c *t*u + 2000*u *x
- t x 4x 2x 4x 4x
- 2 2 2 2
- + 1000*u *c*t + 1200*u *u *c *t*u - 2000*u - 1600*u *c *t*u
- 3x 3x x 3x 2x
- 2 2 2 4 2 4
- - 2000*u *u *b*c*t + 2800*u *u *c *t + 90*u *u *b*c *t *u
- 2x x 2x x 2x x
- 2 2 2 5 2 4
- - 600*u *u *b*c *t*u *x + 1000*u *u *b*x - 180*u *u *c *t *u
- 2x x 2x x 2x x
- 3 2 2 3 3
- + 1200*u *u *c *t*u *x - 2000*u *u *c*x - 600*u *c *t*u
- 2x x 2x x 2x
- 2 2 2 3 2 2
- + 2000*u *c*u*x - 2000*u *a*c*t*u + 600*u *c *t*u + 1000*u *c*x
- 2x x x x
- 4 2 6 2 4 2 2 6 2 6
- + 90*u *a*c *t *u - 600*u *a*c *t*u *x + 1000*u *a*u *x - 27*u *c *t *u
- x x x x
- 4 4 2 2 2 4 5
- + 180*u *c *t*u *x - 300*u *c *u *x - 2000*u *c*u - 36*c *t*u
- x x x
- 2 3
- + 200*c *u *x)/c, x )
- ======================================================
- Conservation law:
- 1 2 7 3 2
- a= - ---*b + ----*b*c - ----*c ,
- 5 10 10
- 1 2 2 7 2
- ( -100 ) * ( u + u + u *c*u + u *u *b - ---*u *b *u + ----*u *b*c*u
- t 5x 3x 2x x 5 x 10 x
- 3 2 2
- - ----*u *c *u )
- 10 x
- =
- df( - 100*u, t )
- +
- 2 2 2 4
- df( - 100*u - 100*u *c*u - 50*u *b + 50*u *c - 20*u *a*b *t*u
- 4x 2x x x x
- 4 2 4 2 4 4
- + 70*u *a*b*c*t*u - 30*u *a*c *t*u - 100*u *a*u *x - 4*u *b *t*u
- x x x x
- 3 4 2 2 4 2 2 3 4
- + 28*u *b *c*t*u - 61*u *b *c *t*u - 20*u *b *u *x + 42*u *b*c *t*u
- x x x x
- 2 4 4 2 2 20 2 3 70 3
- + 70*u *b*c*u *x - 9*u *c *t*u - 30*u *c *u *x + ----*b *u - ----*b*c*u
- x x x 3 3
- 2 3
- + 10*c *u , x )
- ======================================================
- Conservation law:
- 1 2 7 3 2
- a= - ---*b + ----*b*c - ----*c ,
- 5 10 10
- 2 2
- ( - 1000*u - 200*b*u + 100*c*u ) * ( u + u + u *c*u + u *u *b
- 2x t 5x 3x 2x x
- 1 2 2 7 2 3 2 2
- - ---*u *b *u + ----*u *b*c*u - ----*u *c *u )
- 5 x 10 x 10 x
- =
- 2 200 3 100 3
- df( 500*u - -----*b*u + -----*c*u , t )
- x 3 3
- +
- 2 2 2
- df( - 1000*u *u - 1000*u *u - 200*u *b*u + 100*u *c*u + 500*u
- t x 4x 2x 4x 4x 3x
- 2 2 2
- + 400*u *u *b*u - 200*u *u *c*u - 200*u *b*u - 400*u *c*u - 400*u *u *b
- 3x x 3x x 2x 2x 2x x
- 2 3 2 3 2 2
- + 200*u *u *c - 200*u *b*c*u + 100*u *c *u - 1000*u *a*u
- 2x x 2x 2x x
- 2 2 2 2 2 2 2 2 3 6
- - 200*u *b *u + 700*u *b*c*u - 300*u *c *u - 40*u *a*b *t*u
- x x x x
- 2 6 2 6 4 3 6
- + 160*u *a*b *c*t*u - 130*u *a*b*c *t*u - 200*u *a*b*u *x + 30*u *a*c *t*u
- x x x x
- 4 5 6 4 6 3 2 6
- + 100*u *a*c*u *x - 8*u *b *t*u + 60*u *b *c*t*u - 150*u *b *c *t*u
- x x x x
- 3 4 2 3 6 2 4 4 6
- - 40*u *b *u *x + 145*u *b *c *t*u + 160*u *b *c*u *x - 60*u *b*c *t*u
- x x x x
- 2 4 5 6 3 4 3 5 2 5
- - 130*u *b*c *u *x + 9*u *c *t*u + 30*u *c *u *x + 8*b *u - 32*b *c*u
- x x x
- 2 5 3 5
- + 26*b*c *u - 6*c *u , x )
- ======================================================
- Conservation law:
- 1 2 7 3 2
- a= - ---*b + ----*b*c - ----*c ,
- 5 10 10
- 2 2 2 2 2
- ( ( - 2000*u *b*t + 6000*u *c*t - 400*b *t*u + 1400*b*c*t*u - 600*c *t*u
- 2x 2x
- 1 2 2
- - 2000*x)/(b - 3*c) ) * ( u + u + u *c*u + u *u *b - ---*u *b *u
- t 5x 3x 2x x 5 x
- 7 2 3 2 2
- + ----*u *b*c*u - ----*u *c *u )
- 10 x 10 x
- =
- 2 2 400 2 3 1400 3 2 3
- df( (1000*u *b*t - 3000*u *c*t - -----*b *t*u + ------*b*c*t*u - 200*c *t*u
- x x 3 3
- - 2000*u*x)/(b - 3*c), t )
- +
- df( ( - 2000*u *u *b*t + 6000*u *u *c*t - 2000*u *u *b*t + 6000*u *u *c*t
- t x t x 4x 2x 4x 2x
- 2 2 2 2 2
- - 400*u *b *t*u + 1400*u *b*c*t*u - 600*u *c *t*u - 2000*u *x
- 4x 4x 4x 4x
- 2 2 2
- + 1000*u *b*t - 3000*u *c*t + 800*u *u *b *t*u - 2800*u *u *b*c*t*u
- 3x 3x 3x x 3x x
- 2 2 2 2
- + 1200*u *u *c *t*u + 2000*u - 400*u *b *t*u + 400*u *b*c*t*u
- 3x x 3x 2x 2x
- 2 2 2 2 2
- + 2400*u *c *t*u - 800*u *u *b *t + 2800*u *u *b*c*t
- 2x 2x x 2x x
- 2 2 2 3 2 3
- - 1200*u *u *c *t - 400*u *b *c*t*u + 1400*u *b*c *t*u
- 2x x 2x 2x
- 3 3 2 2 2 2
- - 600*u *c *t*u - 2000*u *c*u*x - 2000*u *a*b*t*u + 6000*u *a*c*t*u
- 2x 2x x x
- 2 3 2 2 2 2 2 2 2 2
- - 400*u *b *t*u + 2600*u *b *c*t*u - 4800*u *b*c *t*u - 1000*u *b*x
- x x x x
- 2 3 2 2 4 2 6 3 2 6
- + 1800*u *c *t*u + 1000*u *c*x - 40*u *a*b *t *u + 280*u *a*b *c*t *u
- x x x x
- 2 2 2 6 2 4 3 2 6
- - 610*u *a*b *c *t *u - 400*u *a*b *t*u *x + 420*u *a*b*c *t *u
- x x x
- 4 4 2 6 2 4
- + 1400*u *a*b*c*t*u *x - 90*u *a*c *t *u - 600*u *a*c *t*u *x
- x x x
- 2 2 6 2 6 5 2 6 4 2 2 6
- - 1000*u *a*u *x - 8*u *b *t *u + 84*u *b *c*t *u - 330*u *b *c *t *u
- x x x x
- 4 4 3 3 2 6 3 4
- - 80*u *b *t*u *x + 595*u *b *c *t *u + 560*u *b *c*t*u *x
- x x x
- 2 4 2 6 2 2 4 2 2 2
- - 495*u *b *c *t *u - 1220*u *b *c *t*u *x - 200*u *b *u *x
- x x x
- 5 2 6 3 4 2 2
- + 189*u *b*c *t *u + 840*u *b*c *t*u *x + 700*u *b*c*u *x
- x x x
- 6 2 6 4 4 2 2 2
- - 27*u *c *t *u - 180*u *c *t*u *x - 300*u *c *u *x + 2000*u *c*u
- x x x x
- 4 5 3 5 2 2 5 400 2 3
- + 16*b *t*u - 112*b *c*t*u + 244*b *c *t*u + -----*b *u *x
- 3
- 3 5 1400 3 4 5 2 3
- - 168*b*c *t*u - ------*b*c*u *x + 36*c *t*u + 200*c *u *x)/(b - 3*c), x
- 3
- )
- ======================================================
- Conservation law:
- b=2*c,
- 2
- ( 4*u ) * ( u + u + u *c*u + 2*u *u *c + u *a*u )
- t 5x 3x 2x x x
- =
- 2
- df( 2*u , t )
- +
- 2 2 4
- df( 4*u *u - 4*u *u + 2*u + 4*u *c*u + a*u , x )
- 4x 3x x 2x 2x
- ======================================================
- Conservation law:
- b=2*c,
- 2
- ( 6 ) * ( u + u + u *c*u + 2*u *u *c + u *a*u )
- t 5x 3x 2x x x
- =
- df( 6*u, t )
- +
- 2 3
- df( 6*u + 6*u *c*u + 3*u *c + 2*a*u , x )
- 4x 2x x
- ======================================================
- Conservation law:
- a=0,
- b=2*c,
- ( 2 ) * ( u + u + u *c*u + 2*u *u *c )
- t 5x 3x 2x x
- =
- df( 2*u, t )
- +
- 2
- df( 2*u + 2*u *c*u + u *c, x )
- 4x 2x x
- ======================================================
- Conservation law:
- a=0,
- b=2*c,
- ( 2*u ) * ( u + u + u *c*u + 2*u *u *c )
- t 5x 3x 2x x
- =
- 2
- df( u , t )
- +
- 2 2
- df( 2*u *u - 2*u *u + u + 2*u *c*u , x )
- 4x 3x x 2x 2x
- ======================================================
- Conservation law:
- - 6 2
- ( ------ ) * ( u + u + u *c*u + u *u *b + u *a*u )
- a t 5x 3x 2x x x
- =
- - 6*u
- df( --------, t )
- a
- +
- 2 2 3
- - 6*u - 6*u *c*u - 3*u *b + 3*u *c - 2*a*u
- 4x 2x x x
- df( ---------------------------------------------------, x )
- a
- ======================================================
- Conservation law:
- a=0,
- ( 2 ) * ( u + u + u *c*u + u *u *b )
- t 5x 3x 2x x
- =
- df( 2*u, t )
- +
- 2 2
- df( 2*u + 2*u *c*u + u *b - u *c, x )
- 4x 2x x x
- ======================================================
- {{{2},
- {2*u,
- 2 2
- 2*df(u,x,4) + 2*df(u,x,2)*c*u + df(u,x) *b - df(u,x) *c}},
- - 6
- {{------},
- a
- - 6*u
- {--------,
- a
- 2 2 3
- - 6*df(u,x,4) - 6*df(u,x,2)*c*u - 3*df(u,x) *b + 3*df(u,x) *c - 2*a*u
- -------------------------------------------------------------------------}},
- a
- {{2*u},
- 2
- {u ,
- 2 2
- 2*df(u,x,4)*u - 2*df(u,x,3)*df(u,x) + df(u,x,2) + 2*df(u,x,2)*c*u }},
- {{2},
- {2*u,
- 2
- 2*df(u,x,4) + 2*df(u,x,2)*c*u + df(u,x) *c}},
- {{6},
- {6*u,
- 2 3
- 6*df(u,x,4) + 6*df(u,x,2)*c*u + 3*df(u,x) *c + 2*a*u }},
- {{4*u},
- 2
- {2*u ,
- 2 2 4
- 4*df(u,x,4)*u - 4*df(u,x,3)*df(u,x) + 2*df(u,x,2) + 4*df(u,x,2)*c*u + a*u }
- },
- 2 2 2
- {{(200*( - 10*df(u,x,2)*b*t + 30*df(u,x,2)*c*t - 2*b *t*u + 7*b*c*t*u
- 2 2
- - 3*c *t*u - 10*x))/(b - 3*c)},
- 2 2 2 3 3 2 3
- {(200*(15*df(u,x) *b*t - 45*df(u,x) *c*t - 2*b *t*u + 7*b*c*t*u - 3*c *t*u
- - 30*u*x))/(3*(b - 3*c)),
- ( - 6000*df(u,t)*df(u,x)*b*t + 18000*df(u,t)*df(u,x)*c*t
- - 6000*df(u,x,4)*df(u,x,2)*b*t + 18000*df(u,x,4)*df(u,x,2)*c*t
- 2 2 2 2 2
- - 1200*df(u,x,4)*b *t*u + 4200*df(u,x,4)*b*c*t*u - 1800*df(u,x,4)*c *t*u
- 2 2
- - 6000*df(u,x,4)*x + 3000*df(u,x,3) *b*t - 9000*df(u,x,3) *c*t
- 2
- + 2400*df(u,x,3)*df(u,x)*b *t*u - 8400*df(u,x,3)*df(u,x)*b*c*t*u
- 2 2 2
- + 3600*df(u,x,3)*df(u,x)*c *t*u + 6000*df(u,x,3) - 1200*df(u,x,2) *b *t*u
- 2 2 2
- + 1200*df(u,x,2) *b*c*t*u + 7200*df(u,x,2) *c *t*u
- 2 2 2
- - 2400*df(u,x,2)*df(u,x) *b *t + 8400*df(u,x,2)*df(u,x) *b*c*t
- 2 2 2 3
- - 3600*df(u,x,2)*df(u,x) *c *t - 1200*df(u,x,2)*b *c*t*u
- 2 3 3 3
- + 4200*df(u,x,2)*b*c *t*u - 1800*df(u,x,2)*c *t*u - 6000*df(u,x,2)*c*u*x
- 2 2 2 2 2 3 2
- - 6000*df(u,x) *a*b*t*u + 18000*df(u,x) *a*c*t*u - 1200*df(u,x) *b *t*u
- 2 2 2 2 2 2 2
- + 7800*df(u,x) *b *c*t*u - 14400*df(u,x) *b*c *t*u - 3000*df(u,x) *b*x
- 2 3 2 2 4 2 6
- + 5400*df(u,x) *c *t*u + 3000*df(u,x) *c*x - 120*df(u,x)*a*b *t *u
- 3 2 6 2 2 2 6
- + 840*df(u,x)*a*b *c*t *u - 1830*df(u,x)*a*b *c *t *u
- 2 4 3 2 6
- - 1200*df(u,x)*a*b *t*u *x + 1260*df(u,x)*a*b*c *t *u
- 4 4 2 6
- + 4200*df(u,x)*a*b*c*t*u *x - 270*df(u,x)*a*c *t *u
- 2 4 2 2 6 2 6
- - 1800*df(u,x)*a*c *t*u *x - 3000*df(u,x)*a*u *x - 24*df(u,x)*b *t *u
- 5 2 6 4 2 2 6 4 4
- + 252*df(u,x)*b *c*t *u - 990*df(u,x)*b *c *t *u - 240*df(u,x)*b *t*u *x
- 3 3 2 6 3 4
- + 1785*df(u,x)*b *c *t *u + 1680*df(u,x)*b *c*t*u *x
- 2 4 2 6 2 2 4
- - 1485*df(u,x)*b *c *t *u - 3660*df(u,x)*b *c *t*u *x
- 2 2 2 5 2 6 3 4
- - 600*df(u,x)*b *u *x + 567*df(u,x)*b*c *t *u + 2520*df(u,x)*b*c *t*u *x
- 2 2 6 2 6 4 4
- + 2100*df(u,x)*b*c*u *x - 81*df(u,x)*c *t *u - 540*df(u,x)*c *t*u *x
- 2 2 2 4 5 3 5
- - 900*df(u,x)*c *u *x + 6000*df(u,x)*c*u + 48*b *t*u - 336*b *c*t*u
- 2 2 5 2 3 3 5 3
- + 732*b *c *t*u + 400*b *u *x - 504*b*c *t*u - 1400*b*c*u *x
- 4 5 2 3
- + 108*c *t*u + 600*c *u *x)/(3*(b - 3*c))}},
- 2 2
- {{100*( - 10*df(u,x,2) - 2*b*u + c*u )},
- 2 3 3
- 100*(15*df(u,x) - 2*b*u + c*u )
- {-----------------------------------,
- 3
- 2
- - 1000*df(u,t)*df(u,x) - 1000*df(u,x,4)*df(u,x,2) - 200*df(u,x,4)*b*u
- 2 2
- + 100*df(u,x,4)*c*u + 500*df(u,x,3) + 400*df(u,x,3)*df(u,x)*b*u
- 2 2
- - 200*df(u,x,3)*df(u,x)*c*u - 200*df(u,x,2) *b*u - 400*df(u,x,2) *c*u
- 2 2 3
- - 400*df(u,x,2)*df(u,x) *b + 200*df(u,x,2)*df(u,x) *c - 200*df(u,x,2)*b*c*u
- 2 3 2 2 2 2 2
- + 100*df(u,x,2)*c *u - 1000*df(u,x) *a*u - 200*df(u,x) *b *u
- 2 2 2 2 2 3 6
- + 700*df(u,x) *b*c*u - 300*df(u,x) *c *u - 40*df(u,x)*a*b *t*u
- 2 6 2 6 4
- + 160*df(u,x)*a*b *c*t*u - 130*df(u,x)*a*b*c *t*u - 200*df(u,x)*a*b*u *x
- 3 6 4 5 6
- + 30*df(u,x)*a*c *t*u + 100*df(u,x)*a*c*u *x - 8*df(u,x)*b *t*u
- 4 6 3 2 6 3 4
- + 60*df(u,x)*b *c*t*u - 150*df(u,x)*b *c *t*u - 40*df(u,x)*b *u *x
- 2 3 6 2 4 4 6
- + 145*df(u,x)*b *c *t*u + 160*df(u,x)*b *c*u *x - 60*df(u,x)*b*c *t*u
- 2 4 5 6 3 4 3 5
- - 130*df(u,x)*b*c *u *x + 9*df(u,x)*c *t*u + 30*df(u,x)*c *u *x + 8*b *u
- 2 5 2 5 3 5
- - 32*b *c*u + 26*b*c *u - 6*c *u }},
- {{-100},
- { - 100*u,
- 2 2
- ( - 300*df(u,x,4) - 300*df(u,x,2)*c*u - 150*df(u,x) *b + 150*df(u,x) *c
- 2 4 4 2 4
- - 60*df(u,x)*a*b *t*u + 210*df(u,x)*a*b*c*t*u - 90*df(u,x)*a*c *t*u
- 2 4 4 3 4
- - 300*df(u,x)*a*u *x - 12*df(u,x)*b *t*u + 84*df(u,x)*b *c*t*u
- 2 2 4 2 2 3 4
- - 183*df(u,x)*b *c *t*u - 60*df(u,x)*b *u *x + 126*df(u,x)*b*c *t*u
- 2 4 4 2 2 2 3
- + 210*df(u,x)*b*c*u *x - 27*df(u,x)*c *t*u - 90*df(u,x)*c *u *x + 20*b *u
- 3 2 3
- - 70*b*c*u + 30*c *u )/3}},
- 2 2
- 200*( - 10*df(u,x,2)*c*t - 3*c *t*u + 10*x)
- {{----------------------------------------------},
- c
- 2 2 3
- 200*(5*df(u,x) *c*t - c *t*u + 10*u*x)
- {-----------------------------------------,
- c
- ( - 2000*df(u,t)*df(u,x)*c*t - 2000*df(u,x,4)*df(u,x,2)*c*t
- 2 2 2
- - 600*df(u,x,4)*c *t*u + 2000*df(u,x,4)*x + 1000*df(u,x,3) *c*t
- 2 2 2
- + 1200*df(u,x,3)*df(u,x)*c *t*u - 2000*df(u,x,3) - 1600*df(u,x,2) *c *t*u
- 2 2 2
- - 2000*df(u,x,2)*df(u,x) *b*c*t + 2800*df(u,x,2)*df(u,x) *c *t
- 4 2 4 2 2
- + 90*df(u,x,2)*df(u,x)*b*c *t *u - 600*df(u,x,2)*df(u,x)*b*c *t*u *x
- 2 5 2 4
- + 1000*df(u,x,2)*df(u,x)*b*x - 180*df(u,x,2)*df(u,x)*c *t *u
- 3 2 2
- + 1200*df(u,x,2)*df(u,x)*c *t*u *x - 2000*df(u,x,2)*df(u,x)*c*x
- 3 3 2 2
- - 600*df(u,x,2)*c *t*u + 2000*df(u,x,2)*c*u*x - 2000*df(u,x) *a*c*t*u
- 2 3 2 2 4 2 6
- + 600*df(u,x) *c *t*u + 1000*df(u,x) *c*x + 90*df(u,x)*a*c *t *u
- 2 4 2 2 6 2 6
- - 600*df(u,x)*a*c *t*u *x + 1000*df(u,x)*a*u *x - 27*df(u,x)*c *t *u
- 4 4 2 2 2
- + 180*df(u,x)*c *t*u *x - 300*df(u,x)*c *u *x - 2000*df(u,x)*c*u
- 4 5 2 3
- - 36*c *t*u + 200*c *u *x)/c}},
- 2
- {{100*( - 10*df(u,x,2) - 3*c*u )},
- 2 3
- {100*(5*df(u,x) - c*u ),
- 2
- - 1000*df(u,t)*df(u,x) - 1000*df(u,x,4)*df(u,x,2) - 300*df(u,x,4)*c*u
- 2 2
- + 500*df(u,x,3) + 600*df(u,x,3)*df(u,x)*c*u - 800*df(u,x,2) *c*u
- 2 2
- - 1000*df(u,x,2)*df(u,x) *b + 1400*df(u,x,2)*df(u,x) *c
- 3 4 2
- + 90*df(u,x,2)*df(u,x)*b*c *t*u - 300*df(u,x,2)*df(u,x)*b*c*u *x
- 4 4 2 2
- - 180*df(u,x,2)*df(u,x)*c *t*u + 600*df(u,x,2)*df(u,x)*c *u *x
- 2 3 2 2 2 2 2
- - 300*df(u,x,2)*c *u - 1000*df(u,x) *a*u + 300*df(u,x) *c *u
- 3 6 4 5 6
- + 90*df(u,x)*a*c *t*u - 300*df(u,x)*a*c*u *x - 27*df(u,x)*c *t*u
- 3 4 3 5
- + 90*df(u,x)*c *u *x - 18*c *u }},
- {{ - 100*u},
- 2
- { - 50*u ,
- 2
- ( - 200*df(u,x,4)*u + 200*df(u,x,3)*df(u,x) - 100*df(u,x,2)
- 2 3
- + 60*df(u,x,2)*df(u,x)*b*c *t*u - 200*df(u,x,2)*df(u,x)*b*u*x
- 3 3
- - 120*df(u,x,2)*df(u,x)*c *t*u + 400*df(u,x,2)*df(u,x)*c*u*x
- 2 2 5 3
- - 200*df(u,x,2)*c*u + 60*df(u,x)*a*c *t*u - 200*df(u,x)*a*u *x
- 4 5 2 3 2 4
- - 18*df(u,x)*c *t*u + 60*df(u,x)*c *u *x - 15*c *u )/2}},
- {{-100},
- { - 100*u,
- 2 2
- - 100*df(u,x,4) + 30*df(u,x,2)*df(u,x)*b*c *t*u - 100*df(u,x,2)*df(u,x)*b*x
- 3 2
- - 60*df(u,x,2)*df(u,x)*c *t*u + 200*df(u,x,2)*df(u,x)*c*x
- 2 2 4
- - 100*df(u,x,2)*c*u - 50*df(u,x) *c + 30*df(u,x)*a*c *t*u
- 2 4 4 2 2 2 3
- - 100*df(u,x)*a*u *x - 9*df(u,x)*c *t*u + 30*df(u,x)*c *u *x - 10*c *u }},
- 2
- {{3*( - 2*df(u,x,2) - c*u )},
- 2 3
- {3*df(u,x) - c*u ,
- 2 2
- 3*( - 2*df(u,t)*df(u,x) - 2*df(u,x,4)*df(u,x,2) - df(u,x,4)*c*u + df(u,x,3)
- 2 2
- + 2*df(u,x,3)*df(u,x)*c*u - 2*df(u,x,2) *c*u - 2*df(u,x,2)*df(u,x) *b
- 2 2 3 2 2
- + 4*df(u,x,2)*df(u,x) *c - df(u,x,2)*c *u - 2*df(u,x) *a*u )}},
- 2
- - x
- {{-------},
- c
- 2
- - u*x
- {---------,
- c
- 2 2
- ( - df(u,x,4)*x + 2*df(u,x,3)*x - df(u,x,2)*c*u*x - 2*df(u,x,2)
- 2 2 2
- - df(u,x) *c*x + 2*df(u,x)*c*u*x - c*u )/c}},
- {{x},
- {u*x,
- 2
- df(u,x,4)*x - df(u,x,3) + df(u,x,2)*c*u*x + df(u,x) *c*x - df(u,x)*c*u}},
- {{1},
- {u,
- 2
- df(u,x,4) + df(u,x,2)*c*u + df(u,x) *c}},
- {{ - df(c_294,x) + c_303},
- {u*( - df(c_294,x) + c_303),
- df(c_294,t)*u + df(c_294,x,4)*df(u,x) - df(c_294,x,3)*df(u,x,2)
- + df(c_294,x,2)*df(u,x,3) - df(c_294,x)*df(u,x,4) - df(c_303,x,3)*df(u,x)
- + df(c_303,x,2)*df(u,x,2) - df(c_303,x)*df(u,x,3) + df(u,x,4)*c_303
- 2
- - df(u,x,3)*c*c_294*u - df(u,x,2)*df(u,x)*b*c_294 - df(u,x)*a*c_294*u }},
- {{ - 2*df(u,x,2)},
- 2
- {df(u,x) ,
- 2
- - 2*df(u,t)*df(u,x) - 2*df(u,x,4)*df(u,x,2) + df(u,x,3)
- 2 2 2
- - 2*df(u,x,3)*df(u,x)*c*u - 2*df(u,x,2)*df(u,x) *b - 2*df(u,x) *a*u }},
- {{2*u},
- 2
- {u ,
- 2
- 2*df(u,x,4)*u - 2*df(u,x,3)*df(u,x) + df(u,x,2) }},
- 3
- {{----},
- 2
- a
- 3*u
- {-----,
- 2
- a
- 2 3
- 3*df(u,x,4) + 3*df(u,x,2)*c*u + 3*df(u,x) *c + a*u
- -----------------------------------------------------}},
- 2
- a
- - 4*u
- {{--------},
- a
- 2
- - 2*u
- {---------,
- a
- 2 4
- - 4*df(u,x,4)*u + 4*df(u,x,3)*df(u,x) - 2*df(u,x,2) - a*u
- --------------------------------------------------------------}},
- a
- {{ - 4*u},
- 2
- { - 2*u ,
- 2 4
- - 4*df(u,x,4)*u + 4*df(u,x,3)*df(u,x) - 2*df(u,x,2) - a*u }},
- - 3
- {{------},
- a
- 3
- - 3*u - 3*df(u,x,4) - a*u
- {--------,-----------------------}},
- a a
- {{ - df(c_254,x)},
- { - df(c_254,x)*u,
- df(c_254,t)*u + df(c_254,x,4)*df(u,x) - df(c_254,x,3)*df(u,x,2)
- + df(c_254,x,2)*df(u,x,3) - df(c_254,x)*df(u,x,4) + c_259*u}},
- {{ - 2*u},
- 2
- { - u ,
- 2
- - 2*df(u,x,4)*u + 2*df(u,x,3)*df(u,x) - df(u,x,2) }},
- {{-6},
- { - 6*u,
- 2 3
- - 6*df(u,x,4) - 6*df(u,x,2)*c*u - 3*df(u,x) *c - 2*a*u }},
- {{ - 4*u},
- 2
- { - 2*u ,
- 2 2
- - 4*df(u,x,4)*u + 4*df(u,x,3)*df(u,x) - 2*df(u,x,2) - 4*df(u,x,2)*c*u
- 4
- - a*u }},
- {{-6},
- { - 6*u,
- 2 2 3
- - 6*df(u,x,4) - 6*df(u,x,2)*c*u - 3*df(u,x) *b + 3*df(u,x) *c - 2*a*u }},
- 2
- x
- {{----},
- c
- 2
- u*x
- {------,
- c
- 2 2
- (df(u,x,4)*x - 2*df(u,x,3)*x + df(u,x,2)*c*u*x + 2*df(u,x,2)
- 2 2 2
- + df(u,x) *c*x - 2*df(u,x)*c*u*x + c*u )/c}},
- {{ - x},
- { - u*x,
- 2
- - df(u,x,4)*x + df(u,x,3) - df(u,x,2)*c*u*x - df(u,x) *c*x + df(u,x)*c*u}},
- {{1},
- {u,
- 2
- df(u,x,4) + df(u,x,2)*c*u + df(u,x) *c}},
- {{ - df(c_232,x)},
- { - df(c_232,x)*u,
- df(c_232,t)*u + df(c_232,x,4)*df(u,x) - df(c_232,x,3)*df(u,x,2)
- + df(c_232,x,2)*df(u,x,3) - df(c_232,x)*df(u,x,4) + c_236*u}}}
- comment -------------------------------------------------------------
- conlawi can also be used to determine first integrals of ODEs.
- The generality of the ansatz is not just specified by the order.
- For example, the Lorentz system below is a first order system
- therefore any first integrals are zero order expressions.
- The ansatz to be investigated below looks for first integrals of
- the form a1(x,1)+a2(y,t)+a3(x,t)=const. and determines parameters
- s,b,r such that first integrals exist;
- nodepnd {x,y,z,a1,a2,a3,b,s,r}$
- depend x,t$
- depend y,t$
- depend z,t$
- depend a1,x,t$
- depend a2,y,t$
- depend a3,z,t$
- p_t:=a1+a2+a3$
- conlaw1({{df(x,t) = - s*x + s*y,
- df(y,t) = x*z + r*x - y,
- df(z,t) = x*y - b*z},
- {x,y,z},{t}
- },
- {0,0,t,{a1,a2,a3,s,r,b},{}})$
- --------------------------------------------------------------------------
- This is CONLAW1 - a program for calculating conservation laws of DEs
- The DEs under investigation are :
- x = - s*x + s*y
- t
- y =r*x + x*z - y
- t
- z = - b*z + x*y
- t
- for the function(s): x(t), y(t), z(t)
- ======================================================
- A special ansatz of order 0 for the conserved current is investigated.
- Conservation law:
- 1
- s=---*b,
- 2
- b*t
- ( - e ) * ( z + b*z - x*y )
- t
- +
- ( 0 ) * ( y - r*x - x*z + y )
- t
- +
- b*t
- 2*e *x 1 1
- ( ---------- ) * ( x + ---*b*x - ---*b*y )
- b t 2 2
- =
- b*t b*t 2
- - e *b*z + e *x
- df( -----------------------, t )
- b
- ======================================================
- The function c_473(x) is not constant!
- ======================================================
- Conservation law:
- s=0,
- ( 0 ) * ( z + b*z - x*y )
- t
- +
- ( 0 ) * ( y - r*x - x*z + y )
- t
- +
- ( c_473 ) * ( x )
- x t
- =
- df( c_473, t )
- ======================================================
- Conservation law:
- b=1,
- s=1,
- 2*t
- ( - 2*e *z ) * ( z - x*y + z )
- t
- +
- 2*t
- ( 2*e *y ) * ( y - r*x - x*z + y )
- t
- +
- 2*t
- ( - 2*e *r*x ) * ( x + x - y )
- t
- =
- 2*t 2 2*t 2 2*t 2
- df( - e *r*x + e *y - e *z , t )
- ======================================================
- Conservation law:
- b=1,
- r=0,
- 2*t
- ( - 2*e *z ) * ( z - x*y + z )
- t
- +
- 2*t
- ( 2*e *y ) * ( y - x*z + y )
- t
- +
- ( 0 ) * ( x + s*x - s*y )
- t
- =
- 2*t 2 2*t 2
- df( e *y - e *z , t )
- ======================================================
- Conservation law:
- b=1,
- r=0,
- 1
- s=---,
- 2
- t
- ( - e ) * ( z - x*y + z )
- t
- +
- ( 0 ) * ( y - x*z + y )
- t
- +
- t 1 1
- ( 2*e *x ) * ( x + ---*x - ---*y )
- t 2 2
- =
- t 2 t
- df( e *x - e *z, t )
- ======================================================
- Conservation law:
- b=1,
- r=0,
- 1
- s=---,
- 2
- 2*t
- ( - 2*e *z ) * ( z - x*y + z )
- t
- +
- 2*t
- ( 2*e *y ) * ( y - x*z + y )
- t
- +
- 1 1
- ( 0 ) * ( x + ---*x - ---*y )
- t 2 2
- =
- 2*t 2 2*t 2
- df( e *y - e *z , t )
- ======================================================
- The function c_489(x) is not constant!
- ======================================================
- Conservation law:
- b=1,
- r=0,
- s=0,
- 2*t
- ( - 2*e *z ) * ( z - x*y + z )
- t
- +
- 2*t
- ( 2*e *y ) * ( y - x*z + y )
- t
- +
- ( 0 ) * ( x )
- t
- =
- 2*t 2 2*t 2
- df( e *y - e *z , t )
- ======================================================
- Conservation law:
- b=1,
- r=0,
- s=0,
- ( 0 ) * ( z - x*y + z )
- t
- +
- ( 0 ) * ( y - x*z + y )
- t
- +
- ( c_489 ) * ( x )
- x t
- =
- df( c_489, t )
- ======================================================
- {{{0,0,df(c_489,x)},{c_489}},
- 2*t 2*t
- {{ - 2*e *z,2*e *y,0},
- 2*t 2 2
- {e *(y - z )}},
- 2*t 2*t
- {{ - 2*e *z,2*e *y,0},
- 2*t 2 2
- {e *(y - z )}},
- t t
- {{ - e ,0,2*e *x},
- t 2
- {e *(x - z)}},
- 2*t 2*t
- {{ - 2*e *z,2*e *y,0},
- 2*t 2 2
- {e *(y - z )}},
- 2*t
- {{ - 2*e *z,
- 2*t
- 2*e *y,
- 2*t
- - 2*e *r*x},
- 2*t 2 2 2
- {e *( - r*x + y - z )}},
- {{0,0,df(c_473,x)},{c_473}},
- b*t
- b*t 2*e *x
- {{ - e ,0,----------},
- b
- b*t 2
- e *( - b*z + x )
- {--------------------}}}
- b
- clear p_t$
- nodepnd {u,v,r,p_t,x,y,z,a1,a2,a3,b,s,r}$
- end$
- Time for test: 38149 ms, plus GC time: 610 ms
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