NDSolve solves a differential equation numerically. It returns solutions in a form that can be readily used in many different ways. One typical use would be to produce a plot ...

Collect[expr, x] collects together terms involving the same powers of objects matching x. Collect[expr, {x_1, x_2, ...}] collects together terms that involve the same powers ...

ComplexExpand[expr] expands expr assuming that all variables are real. ComplexExpand[expr, {x_1, x_2, ...}] expands expr assuming that variables matching any of the x_i are ...

Standardize[list] shifts and rescales the elements of list to have zero mean and unit sample variance.Standardize[list, f_1] shifts the elements in list by f_1[list] and ...

Together[expr] puts terms in a sum over a common denominator, and cancels factors in the result.

TrigReduce[expr] rewrites products and powers of trigonometric functions in expr in terms of trigonometric functions with combined arguments.

The general principle that Mathematica follows in evaluating expressions is to go on applying transformation rules until the expressions no longer change. This means, for ...

CUDATranspose[mat] transposes input matrix mat.CUDATranspose[mem] transposes input CUDAMemory mem.

BesselSimplify[expr] transforms Bessel functions in expr, trying to either decrease the number of Bessel functions, or convert Bessel functions into more elementary functions.

GammaSimplify[expr] transforms gamma functions in expr, trying to either decrease the number of gamma functions, or convert combinations of them into more elementary ...