> On Mon, Jan 26, 2015 at 10:58 PM, almog yalin
> wrote:
>
>> I'm trying apply the following substitution a(x) = c * b(x) into a'(x)
>>
>> a = sympy.Function('a')
>> b = sympy.Function('b')
>> c = sympy.Symbol('c')
>
I'm trying apply the following substitution a(x) = c * b(x) into a'(x)
a = sympy.Function('a')
b = sympy.Function('b')
c = sympy.Symbol('c')
x = sympy.Symbol('x')
expression = sympy.Derivative(a(x),x)
expression = expression.subs(a(x),c*b(x))
print expression.simplify()
I was expecting to get
>
I have this partial differential equation
http://en.wikipedia.org/wiki/Burgers%27_equation
To which I want to substitute an ansatz that depends just on one variable:
f(xi), where xi is a function of the two independent variables x and t.
After the substitution, I would like to isolate the derivati
