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4^ or ** for exponentiation (2^3 evaluates to 8)
5abs(...) for absolute value (abs(-4) evaluates to 4)
6! for factorial (3! evaluates to 6)
One useful aspect of Maple is that it distinguishes rational values from floating-point (pseudo-real)
values. Compare these statements:
> 2/3;
> 2.0/3.0;
2/3
.6666666667
This gives you the flexibility to choose between approximate or exact answers to many mathematical
questions.
11.2.4 Variables and Equations (Variablen und Gleichungen)
Maple variables are names that generally begin with a letter and are followed by up to 498
alphanumeric or underscore characters; case is significant (eg: x is different from X in Maple). Maple
distinguishes between two kinds of variables. A Maple programming variable (Programmvariable) is a
variable that you have assigned a result to, generally with an assignment statement
(Zuordnungsanweisung):
> x := 2 + 5;
x := 7
> x;
7
The programming variable x now is a label for the result of 2+5.
To clear a variable, you can type:
> unassign('x');
> x;
x
or:
> x := 'x';
> x;
x
The other kind of Maple variable is a mathematical variable or an unassigned variable (Platzhalter).
These exist in the sense of algebraic unknowns, as in the case of:
> z := 2+y;
z := 2 + y
Here, y is a mathematical variable, and z is a programming variable because an expression has been
assigned to it. If we now assign a value to y, y becomes a programming variable, and is no longer an
algebraic unknown:
> y := 5;
y := 5
> z;
7
An equation (Gleichung) is different from an assignment statement (Zuordnungsanweisung). Consider
the difference between:
> a := 2;
a := 2;
105