Valid Symbols
You can use the following symbols when defining a symbolic function:
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Functions
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Supported in Native or FEM mode
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Definitions
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|---|---|---|
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sin(x)
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Native, FEM
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standard trigonometric function.
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cos(x)
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Native, FEM
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standard trigonometric function.
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tan(x)
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Native, FEM
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standard trigonometric function.
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sinh(x)
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Native, FEM
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hyperbolic trigonometric function.
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cosh(x)
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Native, FEM
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hyperbolic trigonometric function.
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tanh(x)
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Native, FEM
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hyperbolic trigonometric function.
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asin(x)
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Native, FEM
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arc sine in range –  /2 to /2. |
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acos(x)
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Native, FEM
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arc cosine in range 0 to . |
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atan(x)
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Native, FEM
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arc tangent in range – /2 to /2. |
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atan2(y,x)
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Native, FEM
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arc tangent of y/x in range – to . |
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exp(x)
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Native, FEM
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exponential function ex.
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ln(x)
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Native, FEM
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natural (base e) logarithm.
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log(x)
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Native, FEM
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base 10 logarithm.
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abs(x)
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Native, FEM
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absolute value. If x>=0 returns x, otherwise –x.
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sqrt(x)
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Native, FEM
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square root.
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min(x,y)
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Native, FEM
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returns the minimum of x and y. If x<y returns x, otherwise y.
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max(x,y)
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Native, FEM
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returns the maximum of x and y. If x>y, returns x, otherwise y.
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sign(x,y)
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Native, FEM
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sign transfer of y to x. If y<0 returns–abs(x), otherwise abs(x).
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mod(x,y)
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Native, FEM
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remainder function, that is x–int(x/y)*y where int() means "integer part of". The sign of the result is always the same as the sign of x.
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if(c,x,y)
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Native, FEM
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"if" test, or switching function. If expression c (the "condition") returns non-zero (true) then the if function returns x, otherwise (if c=0.0) it returns y. Read like this: if c then x else y.
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bound(x,lo,hi)
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Native, FEM
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limits x to be between bounds lo and hi. If x<lo returns lo, if x>hi returns hi, otherwise, returns x. lo must be <=hi.
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dead(x,lo,hi)
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Native, FEM
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provides a "dead zone" when x is between lo and hi. If x<lo returns x–lo, if x>hi, returns x–hi, otherwise returns 0.
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ceil(x)
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Native, FEM
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"ceiling" function, rounds toward positive infinity
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floor(x)
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Native, FEM
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rounds toward negative infinity
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near(x,y,delta)
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Native, FEM
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"nearness" test. Returns 1.0 (true) if x is within delta of y. If abs(x–y)<=delta returns 1.0, otherwise returns 0.0.
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pow(x,y)
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FEM
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exponentiation function x y. The base is x and exponent is y.
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Constants:
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pi
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Native, FEM
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= 3.14159... |
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e
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Native
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 = 2.71828... |
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Arithmetic Operators:
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+
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Native, FEM
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add
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–
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Native, FEM
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subtract, unary minus, negate
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*
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Native, FEM
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multiply
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/
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Native, FEM
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divide
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^
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Native, FEM
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exponentiate
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Logical Operators (these operators return 1.0 for true, 0.0 for false):
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!
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Native, FEM
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unary "not"
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==
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Native, FEM
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equal
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!=
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Native, FEM
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not equal
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<
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Native, FEM
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less than
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>
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Native, FEM
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greater than
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<=
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Native, FEM
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less than or equal to
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>=
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Native, FEM
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greater than or equal to
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&& in Native mode
& in FEM mode
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Native, FEM
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logical AND
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|| in Native mode
| in FEM mode
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Native, FEM
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logical OR
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Grouping Operators:
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( )
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Native, FEM
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parentheses, grouping
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The arguments of trigonometric functions, values returned by inverse trigonometric functions and angle coordinates are interpreted as radians in Native mode and as degrees in FEM mode. For example, if a load is defined as a function of cylindrical coordinates (r, theta, z) with the symbolic function "5 * theta * z", the load will be evaluated differently in FEM mode compared to Native mode. Symbolic functions that use trigonometric expressions such as cos(theta) are evaluated consistently and accurately in both modes. However, trigonometric functions that have linear dimensions as arguments, for example cos(x/L), where x is a coordinate and L is a linear dimension, are evaluated differently.
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Return to Symbolic Function Type.