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Evaluating expressions

GSA allows geometry and loading to be modified or defined using mathematical expressions. These are mathematical expressions which can define a variation as a function of position (x,y,x)

Normal mathematical notation is used in expressions:

e.g. 1000*sin(x) + y^2

Arithmetic operations

The arithmetic operators are

+addition
-subtraction
*multiplication
/division
^raise to power of

Normal operator precedence is followed. The constants pi (3.14...) and g (9.81...) are defined. Parenthesis can be used to clarify the order of operations.

Mathematical functions

The following functions can be used:

sqrt(x)square root
abs(x)absolute value
exp(x)e raised to power of
ln(x)natural logarithm
log(x)base 10 logarithm
sin(x)sine (in radians)
cos(x)cosine (in radians)
tan(x)tangent (in radians)
asin(x)inverse sine (in radians)
acos(x)inverse cosine (in radians)
atan(x)inverse tangent (in radians)
atan(y,x)inverse tangent of (y/x) (in radians)
sinh(x)hyperbolic sine
cosh(x)hyperbolic cosine
tanh(x)hyperbolic tangent
asinh(x)inverse hyperbolic sine
acosh(x)inverse hyperbolic cosine
atanh(x)inverse hyperbolic tangent
radians(x)conversion of degrees to radians
degrees(x)conversion of radians to degrees
floor(x)round a number down to integer value
ceil(x)round a number up to integer value
sign(x)return sign of number
max(x,y)maximum of two numbers
min(x,y)minimum of two numbers

Conditional expressions

Conditional expressions can be specified in the form:

if( condition, true_expression, false_expression )

The conditional operators are >, <, != (or <>), >=, <=, == (or =) and the logical operators are && (and) and || (or). Conditional expressions can be nested.