C expressions can be used for parameter values. Blocks that
allow an expression as a parameter are evaluated only once at the start of the
simulation (T=0) and will be entered as a constant for code generation. To
evaluate an expression at each time step, use the expression block.

#### Mathematical
functions

Mathematical functions — like acos, asin, atan2, cos, cosh,
exp, log, log10, pow, sin, sinh, sqrt, tan, and tanh — can be used for parameter
values. For example:

The product of the input value 3 and the Gain value
2^{3} is shown in the display block.

For information on entering mathematical functions in C
format, see *C:* *A
Software Engineering Approach*, (Springer-Verlag, 1990).

#### Treatment of bitwise XOR
operator

In a C expression, a bitwise XOR operator is denoted as
a ^. For example:

$1 expands to the input value 2, and Embed produces the
bitwise XOR of 2 and 3, which is 1.

#### Treatment of
constants

Embed treats numeric constants a bit differently than
standard C: constants with no decimal point are still considered to be
floating-point numbers.

Embed interprets *pi* as the universal constant
π.