> Using mathematical expressions

Using mathematical expressions
You can enter mathematical expressions in fields that require a numeric value, such as length, radius, or distance. You can also enter the expression in the user input line. These expressions can include:
+, -, *, /
sin, cos, tan, asin, acos, atan
sqrt (square root)
^ (power: x^y where y is an integer)
exp (e^x)
PI (or lower-case pi)
bracket terms
floor(n) (highest integer less than or equal to n; rounds n down to the next integer)
ceil(n) (smallest integer not less than n; rounds n up to the next integer)
Examples
3*(5.5+17.2) = 68.1
sin(45)+3*11.4 = 34.907106781186549
tan(45) = 1.0
1.5^3 = 3.375
floor(42.17) = 42
ceil(28.17) = 29
floor(-2.3) = -3
ceil(-2.7) = -2
Limitations
A mathematical expression can't contain spaces or it will be evaluated as a LISP expression.
LISP variables are not supported in mathematical expressions. For example, (setq a 5) a+3*1.7 returns a LISP error. However, you can still enter LISP expressions into the user input line as you have always done.
You can't specify unit types in your expressions; values are in current units. For example, 3in+5mm returns a LISP error.
The last value stored in a data field history is the result of the expression and not the expression itself. Whereas the history list of the enter-command line stores the expression itself and not the result.
Expressions cannot be used in accumulated data types like vectors. For example, 0,2*3 is not possible.