# probnum.problems¶

Definitions and collection of problems solved by probabilistic numerical methods.

## Classes¶

 `RegressionProblem`(observations, locations[, …]) Regression problem. `InitialValueProblem`(f, t0, tmax, y0[, df, …]) First order ODE initial value problem. `LinearSystem`(A, b[, solution]) Linear system of equations. `QuadratureProblem`(integrand, lower_bd, upper_bd) Numerical computation of an integral.

## probnum.problems.zoo¶

Subpackage offering implementations of standard example problems or convenient interfaces to benchmark problems for probabilistic numerical methods. These test problems are meant for rapid experimentation and prototyping.

### probnum.problems.zoo.diffeq¶

Test problems involving ordinary differential equations.

#### Functions¶

 `threebody`([t0, tmax, y0]) Initial value problem (IVP) based on a three-body problem. `vanderpol`([t0, tmax, y0, params]) Initial value problem (IVP) based on the Van der Pol Oscillator, implemented in jax. `rigidbody`([t0, tmax, y0, params]) Initial value problem (IVP) for rigid body dynamics without external forces `threebody_jax`([tmax]) Initial value problem (IVP) based on a three-body problem. `vanderpol_jax`([t0, tmax, y0, params]) Initial value problem (IVP) based on the Van der Pol Oscillator, implemented in jax.

### probnum.problems.zoo.linalg¶

Test problems from linear algebra.

#### Functions¶

 `random_spd_matrix`(dim[, spectrum, random_state]) Random symmetric positive definite matrix. `random_sparse_spd_matrix`(dim, density[, …]) Random sparse symmetric positive definite matrix. `suitesparse_matrix`(name, group[, verbose]) Sparse matrix from the SuiteSparse Matrix Collection.

#### Classes¶

 `SuiteSparseMatrix`(matid, group, name, nnz, …) SuiteSparse Matrix.