@@ -724,268 +724,40 @@ The Equation Description tab contains a list of equation elements used in **IGMA
| `sin(a)` | Returns the trigonometric sine of an angle.<br>Special cases: <ul><li>If the argument is `NaN` or an infinity, then the result is `NaN`.</li><li>If the argument is zero, then the result is a zero with the same sign as the argument.</li></ul><br>The computed result must be within 1 ulp of the exact result. Results must be semi-monotonic. | `sin(a)`| `a` - an angle, in radians | the sine of the argument |
| `cos(a)` | Returns the trigonometric cosine of an angle.<br>Special cases: <ul><li>If the argument is `NaN` or an infinity, then the result is `NaN`.</li></ul><br>The computed result must be within 1 ulp of the exact result. Results must be semi-monotonic. | `cos(a)`| `a` - an angle, in radians | the cosine of the argument |
| `tan(a)` | Returns the trigonometric tangent of an angle.<br>Special cases: <ul><li>If the argument is `NaN` or an infinity, then the result is `NaN`.</li><li>If the argument is zero, then the result is a zero with the same sign as the argument.</li></ul><br>The computed result must be within 1 ulp of the exact result. Results must be semi-monotonic. | `tan(a)`| `a` - an angle, in radians | the tangent of the argument |
| `sinh(x)` | Returns the hyperbolic sine of a double value.<br>The hyperbolic sine of `x` is defined to be `(e^x - e^{-x})/2` where `e` is Euler's number.<br>Special cases: <ul><li>If the argument is `NaN`, then the result is `NaN`.</li><li>If the argument is infinite, then the result is an infinity with the same sign as the argument.</li><li>If the argument is zero, then the result is a zero with the same sign as the argument.</li></ul>.<br>The computed result must be within 2.5 ulps of the exact result. | `sinh(x)`| `x` - the number whose hyperbolic sine is to be returned | the hyperbolic sine of the argument |
| `cosh(x)` | Returns the hyperbolic cosine of a double value.<br>The hyperbolic cosine of `x` is defined to be `(e^x + e^{-x})/2` where `e` is Euler's number.<br>Special cases: <ul><li>If the argument is `NaN`, then the result is `NaN`.</li><li>If the argument is infinite, then the result is a positive infinity.</li><li>If the argument is zero, then the result is 1.0.</li></ul>.<br>The computed result must be within 2.5 ulps of the exact result. | `cosh(x)`| `x` - the number whose hyperbolic cosine is to be returned | the hyperbolic cosine of the argument |
| `tanh(x)` | Returns the hyperbolic tangent of a double value.<br>The hyperbolic tangent of `x` is defined to be `(e^x - e^{-x})/(e^x + e^{-x})`, in other words, `sinh(x)/cosh(x)`.<br>Note that the absolute value of the exact `tanh` is always less than 1.<br>Special cases: <ul><li>If the argument is `NaN`, then the result is `NaN`.</li><li>If the argument is infinite, then the result is an infinity with the same sign as the argument.</li><li>If the argument is zero, then the result is a zero with the same sign as the argument.</li><li>If the argument is positive infinity, then the result is +1.0.</li><li>If the argument is negative infinity, then the result is -1.0.</li></ul><br>The computed result must be within 2.5 ulps of the exact result. | `tanh(x)`| `x` - the number whose hyperbolic tangent is to be returned | the hyperbolic tangent of the argument |
| `asin(a)` | Returns the arc sine of a value; the returned angle is in the range -pi/2 through pi/2 | `asin(a)`| `a` - the value whose arc sine is to be returned | the arc sine of the argument |
| `acos(a)` | Returns the arc cosine of a value; the returned angle is in the range 0.0 through pi | `acos(a)`| `a` - the value whose arc cosine is to be returned | the arc cosine of the argument |
| `atan(a)` | Returns the arc tangent of a value; the returned angle is in the range -pi/2 through pi/2 | `atan(a)`| `a` - the value whose arc tangent is to be returned | the arc tangent of the argument |
| `atan2(y, x)` | Returns the angle theta from the conversion of rectangular coordinates (x, y) to polar coordinates (r, theta) | `atan2(y, x)`| `y` - y-coordinate, `x` - x-coordinate | the arc tangent of the argument |
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Function
asin(a)
Returns the arc sine of a value; the returned angle is in the range -pi/2 through pi/2. Special cases:
If the argument is NaN or its absolute value is greater than 1, then the result is NaN.
If the argument is zero, then the result is a zero with the same sign as the argument.
The computed result must be within 1 ulp of the exact result. Results must be semi-monotonic.
Parameters:
a - the value whose arc sine is to be returned.
Returns:
the arc sine of the argument.
Function
acos(a)
Returns the arc cosine of a value; the returned angle is in the range 0.0 through pi. Special cases:
If the argument is NaN or its absolute value is greater than 1, then the result is NaN.
The computed result must be within 1 ulp of the exact result. Results must be semi-monotonic.
Parameters:
a - the value whose arc cosine is to be returned.
Returns:
the arc cosine of the argument.
Function
atan(a)
Returns the arc tangent of a value; the returned angle is in the range -pi/2 through pi/2. Special cases:
If the argument is NaN, then the result is NaN.
If the argument is zero, then the result is a zero with the same sign as the argument.
The computed result must be within 1 ulp of the exact result. Results must be semi-monotonic.
Parameters:
a - the value whose arc tangent is to be returned.
Returns:
the arc tangent of the argument.
Function
atan2(y, x)
Returns the angle theta from the conversion of rectangular coordinates (x, y) to polar coordinates (r, theta). This method computes the phase theta by computing an arc tangent of y/x in the range of -pi to pi. Special cases:
If either argument is NaN, then the result is NaN.
If the first argument is positive zero and the second argument is positive, or the first argument is positive and finite and the second argument is positive infinity, then the result is positive zero.
If the first argument is negative zero and the second argument is positive, or the first argument is negative and finite and the second argument is positive infinity, then the result is negative zero.
If the first argument is positive zero and the second argument is negative, or the first argument is positive and finite and the second argument is negative infinity, then the result is the double value closest to pi.
If the first argument is negative zero and the second argument is negative, or the first argument is negative and finite and the second argument is negative infinity, then the result is the double value closest to -pi.
If the first argument is positive and the second argument is positive zero or negative zero, or the first argument is positive infinity and the second argument is finite, then the result is the double value closest to pi/2.
If the first argument is negative and the second argument is positive zero or negative zero, or the first argument is negative infinity and the second argument is finite, then the result is the double value closest to -pi/2.
If both arguments are positive infinity, then the result is the double value closest to pi/4.
If the first argument is positive infinity and the second argument is negative infinity, then the result is the double value closest to 3*pi/4.
If the first argument is negative infinity and the second argument is positive infinity, then the result is the double value closest to -pi/4.
If both arguments are negative infinity, then the result is the double value closest to -3*pi/4.
The computed result must be within 2 ulps of the exact result. Results must be semi-monotonic.
Parameters:
y - the ordinate coordinate.
x - the abscissa coordinate .
Returns:
the theta component of the point (r, theta) in polar coordinates that corresponds to the point (x, y) in Cartesian coordinates.
Function
deg(x)
Converts an angle measured in radians to an approximately equivalent angle measured in degrees. The conversion from radians to degrees is generally inexact; users should not expect cos(toRadians(90.0)) to exactly equal 0.0.
Parameters:
x - an angle, in radians.
Returns:
the measurement of the angle angrad in degrees.
Function
rad(x)
Converts an angle measured in degrees to an approximately equivalent angle measured in radians. The conversion from degrees to radians is generally inexact.
Parameters:
x - an angle, in degrees.
Returns:
the measurement of the angle angdeg in radians.
Function
abs(a)
Returns the absolute value of a double value. If the argument is not negative, the argument is returned. If the argument is negative, the negation of the argument is returned. Special cases:
If the argument is positive zero or negative zero, the result is positive zero.
Parameters:
a - the argument whose absolute value is to be determined
Returns:
the absolute value of the argument.
Function
round(a)
Returns the closest int to the argument. The result is rounded to an integer by adding 1/2, taking the floor of the result, and casting the result to type int. Special cases:
If the argument is NaN, the result is 0.
If the argument is negative infinity or any value less than or equal to the value of Integer.MIN_VALUE, the result is equal to the value of Integer.MIN_VALUE.
If the argument is positive infinity or any value greater than or equal to the value of Integer.MAX_VALUE, the result is equal to the value of Integer.MAX_VALUE.
Parameters:
a - a floating-point value to be rounded to an integer.
Returns:
the value of the argument rounded to the nearest int value.
Function
ceil(a)
Returns the smallest (closest to negative infinity) double value that is greater than or equal to the argument and is equal to a mathematical integer.
Parameters:
a - a value.
Returns:
the smallest (closest to negative infinity) floating-point value that is greater than or equal to the argument and is equal to a mathematical integer.
Function
floor(a)
Returns the largest (closest to positive infinity) double value that is less than or equal to the argument and is equal to a mathematical integer.
Parameters:
a - a value.
Returns:
the largest (closest to positive infinity) floating-point value that less than or equal to the argument and is equal to a mathematical integer.
Function
exp(a)
Returns Euler's number e raised to the power of a double value. Special cases:
If the argument is NaN, the result is NaN.
If the argument is positive infinity, then the result is positive infinity.
If the argument is negative infinity, then the result is positive zero.
The computed result must be within 1 ulp of the exact result. Results must be semi-monotonic.
Parameters:
a - the exponent to raise e to.
Returns:
the value ea, where e is the base of the natural logarithms.
Function
ln(a)
Returns the natural logarithm (base e) of a double value. Special cases:
If the argument is NaN or less than zero, then the result is NaN.
If the argument is positive infinity, then the result is positive infinity.
If the argument is positive zero or negative zero, then the result is negative infinity.
The computed result must be within 1 ulp of the exact result. Results must be semi-monotonic.
Parameters:
a - a value
Returns:
the value ln a, the natural logarithm of a.
Function
log(a)
Returns the base 10 logarithm of a double value. Special cases:
If the argument is NaN or less than zero, then the result is NaN.
If the argument is positive infinity, then the result is positive infinity.
If the argument is positive zero or negative zero, then the result is negative infinity.
If the argument is equal to 10n for integer n, then the result is n.
The computed result must be within 1 ulp of the exact result. Results must be semi-monotonic.
Parameters:
a - a value
Returns:
the base 10 logarithm of a.
Function
sqrt(a)
Returns the correctly rounded positive square root of a double value. Special cases:
If the argument is NaN or less than zero, then the result is NaN.
If the argument is positive infinity, then the result is positive infinity.
If the argument is positive zero or negative zero, then the result is the same as the argument.
Otherwise, the result is the double value closest to the true mathematical square root of the argument value.
Parameters:
a - a value.
Returns:
the positive square root of a. If the argument is NaN or less than zero, the result is NaN.
Function
min(a, b)
Returns the smaller of two values.
Parameters:
a - an argument.
b - another argument.
Returns:
the smaller of a and b.
Function
max(a, b)
Returns the greater of two values.
Parameters:
a - an argument.
b - another argument.
Returns:
the larger of a and b.
Function
rnd(a)
Generate a Random number (between 0 and given argument).
Parameters:
a - a Value
Returns:
a random Number
Function
sign(a)
Returns the signum function of the argument; zero if the argument is zero, 1.0f if the argument is greater than zero, -1.0f if the argument is less than zero.
Parameters:
a - the floating-point value whose signum is to be returned
Returns:
the signum function of the argument
Function
if(condition, expr1, expr2)
Provides an if-like function: It expects three arguments: A condition, an expression being evaluated if the condition is 1 and an expression which is being evaluated if the condition is not 1.is zero, 1.0f if the argument is greater than zero, -1.0f if the argument is less than zero.
Example:
if(z > -6, exp(z), z)
Parameters:
condition - the condition (, =, =, >=, >, !=)
expr1 - will be evaluated if condition true
expr2 - will be evaluated if condition false
Returns:
the evaluation of the condition
Variable
x
Returns the middle x coordiante of the current cells in the voxelization process.
Returns:
mid x - cell value
Variable
y
Returns the middle y coordiante of the current cells in the voxelization process.
Returns:
mid y - cell value
Variable
z
Returns the middle z coordiante of the current cells in the voxelization process.
Returns:
mid z - cell value
Variable
density
Returns the density value of the Body (subtract by reference density) at Cell Location x, y, z of the current cell in the voxelization process.
Returns:
density - density value subtract by reference density (only if available!)
Variable
susceptibility
Returns the susceptibility value of the Body (subtract by reference susceptibility) at Cell Location x, y, z of the current cell in the voxelization process.
Returns:
susceptibility - susceptibility value subtract by reference susceptibility(only if available!)
Variable
zmin
Gets the lower z - corner of the bounding box from the current Body.
Returns:
z - lower z - corner
Variable
zmax
Gets the upper z - corner of the bounding box from the current Body.
Returns:
z - upper z - corner
Variable
cellvalue
Gets the current Cell Value of the Voxel Cube(for import).
Returns:
cellvalue - the current cell value(0 - if not found)
Variable
ztopo
Gets the deepest Z value at Cell [x,y] of the Interfaces defined in the Bathymetry Tree Node.
Returns:
zbelow - z value at Cell [x,y] -->
| `sinh(x)` | Returns the hyperbolic sine of a double value.<br>The hyperbolic sine of `x` is defined to be $(e^x - e^{-x})/2$ where $e$ is Euler's number.<br>Special cases: <ul><li>If the argument is `NaN`, then the result is `NaN`.</li><li>If the argument is infinite, then the result is an infinity with the same sign as the argument.</li><li>If the argument is zero, then the result is a zero with the same sign as the argument.</li></ul><br>The computed result must be within 2.5 ulps of the exact result. | `sinh(x)`| `x` - the number whose hyperbolic sine is to be returned | the hyperbolic sine of the argument |
| `cosh(x)` | Returns the hyperbolic cosine of a double value.<br>The hyperbolic cosine of `x` is defined to be $(e^x + e^{-x})/2$ where $e$ is Euler's number.<br>Special cases: <ul><li>If the argument is `NaN`, then the result is `NaN`.</li><li>If the argument is infinite, then the result is a positive infinity.</li><li>If the argument is zero, then the result is 1.0.</li></ul><br>The computed result must be within 2.5 ulps of the exact result. | `cosh(x)`| `x` - the number whose hyperbolic cosine is to be returned | the hyperbolic cosine of the argument |
| `tanh(x)` | Returns the hyperbolic tangent of a double value.<br>The hyperbolic tangent of `x` is defined to be $(e^x - e^{-x})/(e^x + e^{-x})$, in other words, `sinh(x)/cosh(x)`.<br>Note that the absolute value of the exact `tanh` is always less than 1.<br>Special cases: <ul><li>If the argument is `NaN`, then the result is `NaN`.</li><li>If the argument is infinite, then the result is an infinity with the same sign as the argument.</li><li>If the argument is zero, then the result is a zero with the same sign as the argument.</li><li>If the argument is positive infinity, then the result is +1.0.</li><li>If the argument is negative infinity, then the result is -1.0.</li></ul><br>The computed result must be within 2.5 ulps of the exact result. | `tanh(x)`| `x` - the number whose hyperbolic tangent is to be returned | the hyperbolic tangent of the argument |
| `asin(a)` | Returns the arc sine of a value; the returned angle is in the range $-\pi/2$ through $\pi/2$.<br>Special cases: <ul><li>If the argument is `NaN` or its absolute value is greater than 1, then the result is `NaN`.</li><li>If the argument is zero, then the result is a zero with the same sign as the argument.</li></ul><br>The computed result must be within 1 ulp of the exact result. Results must be semi-monotonic. | `asin(a)`| `a` - the value whose arc sine is to be returned | the arc sine of the argument |
| `acos(a)` | Returns the arc cosine of a value; the returned angle is in the range 0.0 through $\pi$.<br>Special cases: <ul><li>If the argument is `NaN` or its absolute value is greater than 1, then the result is `NaN`.</li></ul><br>The computed result must be within 1 ulp of the exact result. Results must be semi-monotonic. | `acos(a)`| `a` - the value whose arc cosine is to be returned | the arc cosine of the argument |
| `atan(a)` | Returns the arc tangent of a value; the returned angle is in the range $-\pi/2$ through $\pi/2$.<br>Special cases: <ul><li>If the argument is `NaN`, then the result is `NaN`.</li><li>If the argument is zero, then the result is a zero with the same sign as the argument.</li></ul><br>The computed result must be within 1 ulp of the exact result. Results must be semi-monotonic. | `atan(a)`| `a` - the value whose arc tangent is to be returned | the arc tangent of the argument |
| `atan2(y, x)` | Returns the angle theta from the conversion of rectangular coordinates $(x, y)$ to polar coordinates $(r, \theta)$.<br>This method computes the phase $\theta$ by computing an arc tangent of `y/x` in the range of $-\pi$ to $\pi$.<br>Special cases: <ul><li>If the argument is `NaN`, then the result is `NaN`.</li><li>If the first argument is positive zero and the second argument is positive, or the first argument is positive and finite and the second argument is positive infinity, then the result is positive zero.</li><li>If the first argument is negative zero and the second argument is positive, or the first argument is negative and finite and the second argument is positive infinity, then the result is negative zero.</li><li>If the first argument is positive zero and the second argument is negative, or the first argument is positive and finite and the second argument is negative infinity, then the result is the double value closest to $\pi$.</li><li>If the first argument is negative zero and the second argument is negative, or the first argument is negative and finite and the second argument is negative infinity, then the result is the double value closest to $-\pi$.<li>If the first argument is positive and the second argument is positive zero or negative zero, or the first argument is positive infinity and the second argument is finite, then the result is the double value closest to $\pi/2$.</li><li>If the first argument is negative and the second argument is positive zero or negative zero, or the first argument is negative infinity and the second argument is finite, then the result is the double value closest to $-\pi/2$.</li><li>If both arguments are positive infinity, then the result is the double value closest to $\pi/4$.</li><li>If the first argument is positive infinity and the second argument is negative infinity, then the result is the double value closest to $3\pi/4$.</li><li>If the first argument is negative infinity and the second argument is positive infinity, then the result is the double value closest to $-\pi/4$.</li><li>If both arguments are negative infinity, then the result is the double value closest to $-3\pi/4$.</li></ul><br>The computed result must be within 2 ulps of the exact result. Results must be semi-monotonic. | `atan2(y, x)`| `y` - the ordinate coordinate, `x` - the abscissa coordinate | the theta component of the point $(r, \theta)$ in polar coordinates that corresponds to the point $(x, y)$ in Cartesian coordinates. |
| `deg(x)` | Converts an angle measured in radians to an approximately equivalent angle measured in degrees.<br>The conversion from radians to degrees is generally inexact; users should not expect `cos(toRadians(90.0))` to exactly equal 0.0. | `deg(x)` | `x` - an angle, in radians | the measurement of the argument in degrees |
| `rad(x)` | Converts an angle measured in degrees to an approximately equivalent angle measured in radians.<br>The conversion from degrees to radians is generally inexact. | `rad(x)` | `x` - an angle, in degrees | the measurement of the argument in radians |
| `abs(a)` | Returns the absolute value of a double value.<br>If the argument is not negative, the argument is returned.<br>If the argument is negative, the negation of the argument is returned.<br>Special cases: <ul><li>If the argument is positive zero or negative zero, the result is positive zero.</li></ul> | `abs(a)` | `a` - the argument whose absolute value is to be determined | the absolute value of the argument |
| `round(a)` | Returns the closest int to the argument.<br>The result is rounded to an integer by adding 1/2, taking the floor of the result, and casting the result to type `int`.<br>Special cases: <ul><li>If the argument is NaN, the result is 0.</li><li>If the argument is negative infinity or any value less than or equal to the value of `Integer.MIN_VALUE`, the result is equal to the value of `Integer.MIN_VALUE`.</li><li>If the argument is positive infinity or any value greater than or equal to the value of `Integer.MAX_VALUE`, the result is equal to the value of `Integer.MAX_VALUE`.</li></ul> | `round(a)` | `a` - a floating-point value to be rounded to an integer | the value of the argument rounded to the nearest `int` value |
| `ceil(a)` | Returns the smallest (closest to negative infinity) double value that is greater than or equal to the argument and is equal to a mathematical integer. | `ceil(a)` | `a` - a value | the smallest (closest to negative infinity) floating-point value that is greater than or equal to the argument and is equal to a mathematical integer |
| `floor(a)` | Returns the largest (closest to positive infinity) double value that is less than or equal to the argument and is equal to a mathematical integer. | `floor(a)`| `a` - a value | the largest (closest to positive infinity) floating-point value that less than or equal to the argument and is equal to a mathematical integer |
| `exp(a)` | Returns Euler's number $e$ raised to the power of a double value.<br>Special cases: <ul><li>If the argument is `NaN`, the result is `NaN`.</li><li>If the argument is positive infinity, then the result is positive infinity.</li><li>If the argument is negative infinity, then the result is positive zero.</li></ul><br>The computed result must be within 1 ulp of the exact result. Results must be semi-monotonic. | `exp(a)` | `a` - the exponent to raise $e$ to | the value $e^a$, where $e$ is the base of the natural logarithm |
| `ln(a)` | Returns the natural logarithm (base $e$) of a double value.<br>Special cases:<ul><li>If the argument is `NaN` or less than zero, then the result is `NaN`.</li><li>If the argument is positive infinity, then the result is positive infinity.</li><li>If the argument is positive zero or negative zero, then the result is negative infinity.</li></ul><br>The computed result must be within 1 ulp of the exact result. Results must be semi-monotonic. | `ln(a)` | `a` - a value | the value `ln a`, the natural logarithm of `a` |
| `log(a)` | Returns the base 10 logarithm of a double value.<br>Special cases:<ul><li>If the argument is `NaN` or less than zero, then the result is `NaN`.</li><li>If the argument is positive infinity, then the result is positive infinity.</li><li>If the argument is positive zero or negative zero, then the result is negative infinity.</li><li>If the argument is equal to `10n` for integer `n`, then the result is `n`.</li></ul><br>The computed result must be within 1 ulp of the exact result. Results must be semi-monotonic. | `log(a)` | `a` - a value | the base 10 logarithm of `a` |
| `sqrt(a)` | Returns the correctly rounded positive square root of a double value.<br>Special cases:<ul><li>If the argument is `NaN` or less than zero, then the result is `NaN`.</li><li>If the argument is positive infinity, then the result is positive infinity.</li><li>If the argument is positive zero or negative zero, then the result is the same as the argument.</li></ul><br>Otherwise, the result is the double value closest to the true mathematical square root of the argument value. | `sqrt(a)` | `a` - a value | the positive square root of `a` |
| `min(a, b)` | Returns the smaller of two values. | `min(a, b)` | `a` - an argument, `b` - another argument | the smaller of `a` and `b` |
| `max(a, b)` | Returns the larger of two values. | `max(a, b)` | `a` - an argument, `b` - another argument | the larger of `a` and `b` |
| `rnd(a)` | Generate a random number (between 0 and a given argument) | `rnd(a)` | `a` - a value | a random number |
| `sign(a)` | Returns the signum function of the argument; zero if the argument is zero, `1.0f` if the argument is greater than zero, `-1.0f` if the argument is less than zero. | `sign(a)` | `a` - the floating-point value whose signum is to be returned | the signum function of the argument |
| `if(condition, expr1, expr2)` | Provides an if-like function; it expects three arguments: a condition, an expression being evaluated if the condition is 1 and an expression which is being evaluated if the condition is not 1. | `if(z > -6, exp(z), z)` | `condition` - the condition (`<`, `<=`, `=`, `>=`, `>`, `!=`), `expr1` - will be evaluated if condition is true, `expr2` - will be evaluated if condition false | the evaluation of the condition |
| Variable | Description | Returns |
|:-----------------|:------------|:--------|
| `x` | Returns the middle $x$ coordinate of the current cell in the voxelization process | mid `x` - cell value |
| `y` | Returns the middle $y$ coordinate of the current cell in the voxelization process | mid `y` - cell value |
| `z` | Returns the middle $z$ coordinate of the current cell in the voxelization process | mid `z` - cell value |
| `density` | Returns the density value of the Body (subtract by reference density) at Cell Location $x$, $y$, $z$ of the current cell in the voxelization process | `density` - density value subtract by reference density (only if available!) |
| `susceptibility` | Returns the susceptibility value of the Body (subtract by reference susceptibility) at Cell Location $x$, $y$, $z$ of the current cell in the voxelization process | `susceptibility` - susceptibility value subtract by reference susceptibility(only if available!) |
| `zmin` | Gets the lower $z$ - corner of the bounding box from the current Body | `z` - lower $z$ - corner |
| `zmax` | Gets the upper $z$ - corner of the bounding box from the current Body | `z` - upper $z$ - corner |
| `cellvalue` | Gets the current Cell Value of the Voxel Cube(for import) | `cellvalue` - the current cell value (0 - if not found) |
| `ztopo` | Gets the deepest $z$ value at Cell [$x$,$y$] of the Interfaces defined in the Bathymetry Tree Node | `ztopo` - $z$ value at Cell [$x$,$y$] |
Equation elements are used mainly during the [voxel import](./workflows/voxels.md#import-a-voxel-cube).
