Hello
the solution of the PDE:
df(x,y)/dx + df(x,y)/dy =0
should be f= f(x-y) , with f an arbitrary function of the argument which is the compound variable (x-y).
Wanting to verify this symbolic solution I would like to execute these commands
1) syms x y real
2) syms f(x-y)
and then do the calculation
3) ver=diff(f(x-y),x)+diff(f(x-y),y)
and simplifying it should give
ver=zero

but unfortunately on the second line it
gives me an error :
———————————————————————
Error using symfun.parseString (line 101)
Invalid variable name.

Error in syms (line 276)
[name, vars] = symfun.parseString(x,’allowPercent’);
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
———————————————————————–

I was kindly asking
how to proceed and be able to do this
symbolic verification

thankyou very much !
ValerioHello
the solution of the PDE:
df(x,y)/dx + df(x,y)/dy =0
should be f= f(x-y) , with f an arbitrary function of the argument which is the compound variable (x-y).
Wanting to verify this symbolic solution I would like to execute these commands
1) syms x y real
2) syms f(x-y)
and then do the calculation
3) ver=diff(f(x-y),x)+diff(f(x-y),y)
and simplifying it should give
ver=zero

but unfortunately on the second line it
gives me an error :
———————————————————————
Error using symfun.parseString (line 101)
Invalid variable name.

Error in syms (line 276)
[name, vars] = symfun.parseString(x,’allowPercent’);
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
———————————————————————–

I was kindly asking
how to proceed and be able to do this
symbolic verification

thankyou very much !
Valerio Hello
the solution of the PDE:
df(x,y)/dx + df(x,y)/dy =0
should be f= f(x-y) , with f an arbitrary function of the argument which is the compound variable (x-y).
Wanting to verify this symbolic solution I would like to execute these commands
1) syms x y real
2) syms f(x-y)
and then do the calculation
3) ver=diff(f(x-y),x)+diff(f(x-y),y)
and simplifying it should give
ver=zero

but unfortunately on the second line it
gives me an error :
———————————————————————
Error using symfun.parseString (line 101)
Invalid variable name.

Error in syms (line 276)
[name, vars] = symfun.parseString(x,’allowPercent’);
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
———————————————————————–

I was kindly asking
how to proceed and be able to do this
symbolic verification

thankyou very much !
Valerio symbolic functions MATLAB Answers — New Questions

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