Sign[x] gives -1, 0, or 1 depending on whether x is negative, zero, or positive.

Sum[f, {i, i_max}] evaluates the sum \[Sum]i = 1 i_max f. Sum[f, {i, i_min, i_max}] starts with i = i_min. Sum[f, {i, i_min, i_max, di}] uses steps d i. Sum[f, {i, {i_1, i_2, ...

Text[expr] displays with expr in plain text format. Text[expr, coords] is a graphics primitive that displays the textual form of expr centered at the point specified by ...

With Mathematica's citation management features, you can annotate and add references to research papers written using Mathematica. These features work in conjunction with the ...

Combinatorial functions. The factorial function n! gives the number of ways of ordering n objects. For non-integer n, the numerical value of n! is obtained from the gamma ...

Linear programming problems are optimization problems where the objective function and constraints are all linear. Mathematica has a collection of algorithms for solving ...

When you set up a graphics object in Mathematica, you give coordinates for the various graphical elements that appear. When Mathematica renders the graphics object, it has to ...

Just as the equation x^2+3x==2 asserts that x^2+3x is equal to 2, so also the inequality x^2+3x>2 asserts that x^2+3x is greater than 2. In Mathematica, Reduce works not only ...

Getting parts of lists. This gives a list of parts 1 and 3. Here is a nested list.

An expression like x^2+2x-7==0 represents an equation in Mathematica. You will often need to solve equations like this, to find out for what values of x they are true. This ...