Return[expr] returns the value expr from a function. Return[] returns the value Null.

x - y is equivalent to x + (-1*y).

True is the symbol for the Boolean value true.

Uncompress["string"] recovers an expression from a compressed string representation generated by Compress.Uncompress["string", h] wraps the head h around the expression ...

$BatchInput is True if input in the current session is being fed directly to the Mathematica kernel in batch mode.

$CurrentLink is the LinkObject representing the MathLink connection for an external program currently being installed or being called.

$KernelCount gives the number of subkernels available for parallel computations.

If you have a list of elements, it is often important to be able to apply a function separately to each of the elements. You can do this in Mathematica using Map. This ...

In many kinds of numerical computations, it is convenient to introduce approximate functions. Approximate functions can be thought of as generalizations of ordinary ...

You can define the derivative in Mathematica of a function f of one argument simply by an assignment like f'[x_]=fp[x]. This defines the derivative of f(x) to be fp(x). In ...