GNU Octave Manual Version 3 by John W. Eaton, David Bateman, Søren Hauberg Paperback (6"x9"), 568 pages ISBN 095461206X RRP £24.95 ($39.95) Get a printed copy>>>

GNU Octave Manual Version 3 Buy the book here >>> support free documentation

17.7 Mathematical Constants

Built-in Function: I (x)

Built-in Function: I (n, m)

Built-in Function: I (n, m, k, ...)

Built-in Function: I (..., class)

Return a matrix or N-dimensional array whose elements are all equal to the pure imaginary unit, defined as sqrt (-1).

Since I (also i, J, and j) is a function, you can use the name(s) for other purposes.

Built-in Function: Inf (x)

Built-in Function: Inf (n, m)

Built-in Function: Inf (n, m, k, ...)

Built-in Function: Inf (..., class)

Return a matrix or N-dimensional array whose elements are all Infinity. The arguments are handled the same as the arguments for eye. The optional argument class may be either ‘"single"’ or ‘"double"’. The default is ‘"double"’.

Built-in Function: NaN (x)

Built-in Function: NaN (n, m)

Built-in Function: NaN (n, m, k, ...)

Built-in Function: NaN (..., class)

Return a matrix or N-dimensional array whose elements are all NaN (Not a Number). The value NaN is the result of an operation like 0/0, or ‘Inf - Inf’,

or any operation with a NaN.

Note that NaN always compares not equal to NaN. This behavior is specified by the IEEE standard for floating point arithmetic. To find NaN values, you must use the isnan function.

The arguments are handled the same as the arguments for eye. The optional argument class may be either ‘"single"’ or ‘"double"’. The default is ‘"double"’.

Built-in Function: pi (x)

Built-in Function: pi (n, m)

Built-in Function: pi (n, m, k, ...)

Built-in Function: pi (..., class)

Return a matrix or N-dimensional array whose elements are all equal to the ratio of the circumference of a circle to its diameter. Internally, pi is computed as ‘4.0 * atan (1.0)’.

Built-in Function: e (x)

Built-in Function: e (n, m)

Built-in Function: e (n, m, k, ...)

Built-in Function: e (..., class)

Return a matrix or N-dimensional array whose elements are all equal to the base of natural logarithms. The constant e

satisfies the equation log (e) = 1.

Built-in Function: eps (x)

Built-in Function: eps (n, m)

Built-in Function: eps (n, m, k, ...)

Built-in Function: eps (..., class)

Return a matrix or N-dimensional array whose elements are all eps, the machine precision. More precisely, eps is the largest relative spacing between any two adjacent numbers in the machine's floating point system. This number is obviously system-dependent. On machines that support 64-bit IEEE floating point arithmetic, eps is approximately 2.2204e-16.

Built-in Function: realmax (x)

Built-in Function: realmax (n, m)

Built-in Function: realmax (n, m, k, ...)

Built-in Function: realmax (..., class)

Return a matrix or N-dimensional array whose elements are all equal to the largest floating point number that is representable. The actual value is system-dependent. On machines that support 64-bit IEEE floating point arithmetic, realmax is approximately 1.7977e+308

See also realmin

Built-in Function: realmin (x)

Built-in Function: realmin (n, m)

Built-in Function: realmin (n, m, k, ...)

Built-in Function: realmin (..., class)

Return a matrix or N-dimensional array whose elements are all equal to the smallest normalized floating point number that is representable. The actual value is system-dependent. On machines that support 64-bit IEEE floating point arithmetic, realmin is approximately 2.2251e-308

See also realmax