ais substituted for
c. This is a powerful function with many uses.
First, it may be used to insert numbers for variables, in the example for in der formula .
>> syms x >> a=2*sqrt(x)*exp(-x^2); >> subst(3,x,a) ans = 4.275E-4
Second, one can replace a symbolic variable by a complex term. The expression is automatically updated to the canonical format. In the following example is inserted for in .
>> syms x,z >> p=x^3+2*x^2+x+7; >> subst(z^3+2,x,p) ans = z^9+8*z^6+21*z^3+25
Finally, the term
b itself may be a complex expression
(in the example ). Jasymca then tries to identify this
This is accomplished by solving the equation for
the symbolic variable in
b (example: ), and inserting the
c. This does not always succeed, or
there may be several solutions, which are returned as a vector.
>> syms x,y,z >> c=x^3*z/sqrt(z^2+1); >> d=subst(y,z^2+1,c) d = [ x^3*sqrt(y-1)/sqrt(sqrt(y-1)^2+1) -x^3*sqrt(y-1)/sqrt(sqrt(y-1)^2+1) ] >> d=trigrat(d) d = [ x^3*sqrt(y-1)/sqrt(y) -x^3*sqrt(y-1)/sqrt(y) ]