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The support for solving time-dependent problems is incorporated in the
solution strategy using `solve`

, but only rudimentary. More
precisely, you will have to specify the number of levels for spatial
refinement and several parameters specifying how many time-steps of
which length are done. For example, the following code solves a
one-dimensional heat equation with zero right-hand side and some initial
values:

(storing (solve (blackboard :problem (cdr-model-problem 1 :initial #'(lambda (x) #I(sin(2*pi*x[0]^^2)))) :start-time 0.0 :time-step 0.01 :number-of-time-steps 20 :number-of-levels 6 :plot t :output 1)))

First, the mesh is built up to approximate the initial values until given criteria are met (here the number of levels is prescribed). Then a time-stepping scheme with the BDF2 method and uniform time-steps is used to approximate the solution in time.