Node:Numeric Data Types, Next:Strings, Previous:Data Types, Up:Top
A numeric constant may be a scalar, a vector, or a matrix, and it may contain complex values.
The simplest form of a numeric constant, a scalar, is a single number
that can be an integer, a decimal fraction, a number in scientific
(exponential) notation, or a complex number. Note that all numeric
constants are represented within Octave in double-precision floating
point format (complex constants are stored as pairs of double-precision
floating point values). Here are some examples of real-valued numeric
constants, which all have the same value:
105 1.05e+2 1050e-1
To specify complex constants, you can write an expression of the form
3 + 4i 3.0 + 4.0i 0.3e1 + 40e-1i
all of which are equivalent. The letter i
in the previous example
stands for the pure imaginary constant, defined as
sqrt (-1)
.
For Octave to recognize a value as the imaginary part of a complex
constant, a space must not appear between the number and the i
.
If it does, Octave will print an error message, like this:
octave:13> 3 + 4 i parse error: 3 + 4 i ^
You may also use j
, I
, or J
in place of the
i
above. All four forms are equivalent.