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Inverse Laplace transform
ilaplace(F,trans_var,eval_point)
ilaplace(F,trans_var,eval_point) computes the inverse Laplace transform of F with respect to the transformation variable trans_var at the point eval_point.
Compute the inverse Laplace transform of this expression with respect to the variable y at the evaluation point x:
syms x y F = 1/y^2; ilaplace(F, y, x)
ans = x
Compute the inverse Laplace transform of this expression calling the ilaplace function with one argument. If you do not specify the transformation variable, ilaplace uses the variable s:
syms a s x F = 1/(s - a)^2; ilaplace(F, x)
ans = x*exp(a*x)
If you also do not specify the evaluation point, ilaplace uses the variable t:
ilaplace(F)
ans = t*exp(a*t)
Compute the following inverse Laplace transforms that involve the Dirac and Heaviside functions:
syms s t ilaplace(1, s, t)
ans = dirac(t)
ilaplace(exp(-2*s)/(s^2 + 1) + s/(s^3 + 1), s, t)
ans = heaviside(t - 2)*sin(t - 2) - exp(-t)/3 +... (exp(t/2)*(cos((3^(1/2)*t)/2) + 3^(1/2)*sin((3^(1/2)*t)/2)))/3
If ilaplace cannot find an explicit representation of the transform, it returns an unevaluated call:
syms F(s) t f = ilaplace(F, s, t)
f(t) = ilaplace(F(s), s, t)
laplace returns the original expression:
laplace(f, t, s)
ans(s) = F(s)