Xor[e_1, e_2, ...] is the logical XOR (exclusive OR) function. It gives True if an odd number of the e_i are True, and the rest are False. It gives False if an even number of ...

Finding elements that match a pattern. This gives the elements of the list which match the pattern x^_. Here is the total number of elements which match the pattern.

Low-level functions for converting between expressions and boxes. MakeBoxes generates boxes without evaluating its input. MakeExpression interprets boxes but uses ...

Array[f, n] generates a list of length n, with elements f[i]. Array[f, {n_1, n_2, ...}] generates an n_1*n_2*... array of nested lists, with elements f[i_1, i_2, ...]. ...

Multinomial[n_1, n_2, ...] gives the multinomial coefficient (n_1 + n_2 + ...)!/(n_1! n_2! ...).

ToContinuousTimeModel[sys] gives the continuous-time approximation of the discrete-time TransferFunctionModel or StateSpaceModel object sys.ToContinuousTimeModel[tf, s] gives ...

Although Mathematica matches patterns in a purely structural fashion, its notion of structural equivalence is quite sophisticated. In particular, it takes account of ...

Thread[f[args]] "threads" f over any lists that appear in args. Thread[f[args], h] threads f over any objects with head h that appear in args. Thread[f[args], h, n] threads f ...

Listable is an attribute that can be assigned to a symbol f to indicate that the function f should automatically be threaded over lists that appear as its arguments.

The numerical method of lines is a technique for solving partial differential equations by discretizing in all but one dimension, and then integrating the semi-discrete ...