# Evaluating solutions

`Fronts.Solution`

— TypeSolution to a problem.

```
(::Solution)(r, t)
(::Solution)(o)
```

Evaluate the solution.

**Properties**

`retcode`

: termination status of the solver. See`ReturnCode`

.`i`

: initial value.`b`

: boundary value.`d_dob`

:`o`

-derivative at the boundary, where`o`

is the Boltzmann variable. See also`o`

.`ob`

: boundary constant. See also`rb`

.`oi`

: for`o≥oi`

, the solution evaluates to the initial value.`prob`

: problem solved.`alg`

: algorithm used.`original`

: original solution object, if applicable.

`Fronts.d_dr`

— Function`d_dr(::Solution, r, t)`

Spatial derivative of the solution.

`d_dr(::Solution, :b, t)`

Spatial derivative of the solution at the boundary.

`Fronts.d_dt`

— Function`d_dt(::Solution, r, t)`

Time derivative of the solutio.

`d_dt(::Solution, :b, t)`

Time derivative of the solution at the boundary.

`Fronts.flux`

— Function`flux(::Solution, r, t)`

Flux.

`flux(::Solution, :b, t)`

Boundary flux.

`Fronts.d_do`

— Function```
d_do(::Solution, r, t)
d_do(::Solution, o)
```

`o`

-derivative of the solution, where `o`

is the Boltzmann variable.

See also: `o`

`Fronts.rb`

— Function`rb(::Solution, t)`

Location of the boundary in the solution at time `t`

, equal to `ob*√t`

.

`Fronts.sorptivity`

— Method`sorptivity(::Solution)`

Sorptivity.

`sorptivity(::Solution, o)`

Sorptivity, computed from the given value of o.

**References**

PHILIP, J. R. The theory of infiltration: 4. Sorptivity and algebraic infiltration equations. Soil Science, 1957, vol. 84, no. 3, p. 257-264.

`Fronts.sorptivity`

— Method`sorptivity(::Solution)`

Sorptivity.

`sorptivity(::Solution, o)`

Sorptivity, computed from the given value of o.

**References**

PHILIP, J. R. The theory of infiltration: 4. Sorptivity and algebraic infiltration equations. Soil Science, 1957, vol. 84, no. 3, p. 257-264.

`Fronts.FiniteSolution`

— TypeSolution to a finite problem.

`(::FiniteSolution)(r, t)`

Evaluate the solution at location `r`

and time `t`

.