Language Reference 1: Difference between revisions
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SAMPLE MODELS: | SAMPLE MODELS: | ||
<links to sample models where this function is used> | <links to sample models where this function is used> | ||
[[Model Builder's Guide Chapter 9# | [[Model Builder's Guide Chapter 9#Expressions:]] | ||
(Expr) base of the natural logarithm (e) to the power of | (Expr) base of the natural logarithm (e) to the power of | ||
the expression | the expression | ||
==CEILING== | ==CEILING== | ||
Revision as of 15:20, 10 October 2006
ABS
(Expr) absolute value of the expression Model Builder's Guide Chapter 9#Continuous Functions (Arithmetic Functions)
ABSOLUTE
(Expr) absolute value of the expression
Expr % Expr
value of the first expression modulo the value of the second expression (assumes that the values of the expressions are integers)
AND
TRUE (1) if all sub-expressions evaluate to TRUE and FALSE (0) otherwise Model Builder's Guide Chapter 9#Composite Functions
==ARCCOS==(Expr) inverse cos of the value of the expression Model Builder's Guide Chapter 9#Continuous Functions (Trigonometric Functions)
ARCSIN
(Expr) inverse sine of the value of the expression Model Builder's Guide Chapter 9#Continuous Functions (Trigonometric Functions)
ARCTAN
(Expr) inverse tan of the value of the expression Model Builder's Guide Chapter 9#Continuous Functions (Trigonometric Functions)
ARCTAN
(Expr, Expr) inverse tan where first expression is x offset and second is y offset. Providing two expressions gives more information about the quadrant. Model Builder's Guide Chapter 9#Continuous Functions (Trigonometric Functions)
BITWISE OR
(Expr, Expr) Bitwise OR of two valuesModel Builder's Guide Chapter 9#Bit-Vector Functions
BITWISE AND
(Expr, Expr) Bitwise AND of two valuesModel Builder's Guide Chapter 9#Bit-Vector Functions
BITWISE XOR
(Expr, Expr) Bitwise exclusive-OR of two valuesModel Builder's Guide Chapter 9#Bit-Vector Functions
BITWISE NOT
Expr Bitwise NOT of a valueModel Builder's Guide Chapter 9#Bit-Vector Functions
EXP
Expr^Expr DESCRIPTION: (Expr) base of the natural logarithm (e) to the power of the expression USAGE:
x=Expr^Expr
REQUIRED ARGUMENTS: Expr is any expression that evaluates to single numeric value
VALUE: The first expression to the power of the value of the second expression
SEE ALSO: <a link to the composite functions section of seles modellers guide>
EXAMPLES: <add carriage return here> Example 1:
x=7^3
<figure out an end example indicator. For example, ***>
SAMPLE MODELS: <links to sample models where this function is used> Model Builder's Guide Chapter 9#Expressions:
(Expr) base of the natural logarithm (e) to the power of the expression
CEILING
(Expr) smallest integer larger than the expression valueModel Builder's Guide Chapter 9#Ceiling
CLAMP
(Expr, MinExpr, MaxExpr) clamp the value X of the expression to the range [Min, Max]: if X < Min then return Min; if X < Max return Max. Otherwise return X. Model Builder's Guide Chapter 9#Continuous Functions (Arithmetic Functions)
CLASSIFY
(X) if the value of the variable X is equal to one of CLASS Number: Expr the classes listed, then return the result of the. : associated expression. Otherwise return 0. Model Builder's Guide Chapter 9#Classified and Discrete Functions ENDFN Model Builder's Guide Chapter 9#Classified and Discrete Functions
CLASSIFY
(X) return the result of the kth expression in the list, Expr where k = X – minimum value of the variables
: (this may be non-0 only for layers) :
Model Builder's Guide Chapter 9#Classified and Discrete Functions ENDFN Model Builder's Guide Chapter 9#Classified and Discrete Functions
CLASSIFY
(X): ( Number+) return the kth number in the list, where k = X – minimum value of the variable (this may be non-0 only for layers)Model Builder's Guide Chapter 9#Classified and Discrete Functions
CLASSIFY
(X): Filename uses the table in the named file, which is assumed to consist of class:value pairs. Rarely used. Model Builder's Guide Chapter 9#Classified and Discrete Functions
CLASSIFY
(X): Filename Key uses the table in the named file, which is assumed to consist of class:value pairs. The key is used to specify a sub-table in a multi-table file. Rarely used.
Classified functions use the variable as an index into the list of numbers or expressions that follow. The “CLASS” keyword is optional. This variable must be non-negative. If “CLASS # :” is used, then the number refers to the value of the indexing variable. If a class is not specified for a given value, its expression is implicitly ZERO. Interpolation tables are very similar except that the variable is assumed to be continuous instead of classified. An interpolated value between classes is returned. Lookup tables are also similar, except that both the variable and classes are assumed to be continuous values. An interpolated value between classes is also returned. Rarely used. Model Builder's Guide Chapter 9#Classified and Discrete Functions
CLASSIFIED_DIST
draw a value from a discrete distribution, where CLASS Number: Expr each expression determines the relative : probability of its associated class being drawn. ENDFN The CLASS keyword is optional.
CLASSIFIED_DIST
( Number+) in this form, the classes are assumed to start at zero. Only constant probabilities can be given.
CLASSIFIED_DIST
in this form, the classes are assumed to start at Expr zero : ENDFN
CLASSIFIED_DIST[M]
In this form, the classes in a one-dimensional array M, and so start at zero.
COS
(Expr) interpret the value of the expression as an angle theta in degrees, and return cos(theta) Model Builder's Guide Chapter 9#Continuous Functions (Trigonometric Functions)
CRITICAL SECTION
(Flag) Enter (if Flag is TRUE) or exit (if Flag is FALSE) a critical section. A critical section gives priority to this application, and is used for synchronizing access to shared variables (i.e. shared with another application).Model Builder's Guide Chapter 9#Control Expressions
DEBUG
Update the simulation probe, if it is loaded and The event is selected. Used to debug/verify event behaviour.Model Builder's Guide Chapter 9#Control Expressions
DECISION
Expr approximation of line between end cells Cost surface and least-cost path regions are advanced features that are best understood with an example model. Model Builder's Guide Chapter 9#Region Functions
DECISION
Expr known location indices. If there is a decision expression, then only those cells for which this expression returns TRUE will be included. Model Builder's Guide Chapter 9#Region Functions
==DECISION== Expr location indices stored in one-dimensional X. Model Builder's Guide Chapter 9#Region Functions
==DECISION== Expr location index. If there is a decision expression, then only those cells for which this expression returns TRUE will be included. Model Builder's Guide Chapter 9#Region Functions
DECISION
Expr defines a region centred on the current cell. If there is a decision expression, then only those cells for which this expression returns TRUE will be included.
DistanceType is either CARDINAL or EUCLIDEAN (the default). Cardinal distance between two cells is the minimum number of cardinal steps (up, down, left, right) to reach one cell from the other. Euclidean distance is the straight-line distance between two points. The WRAPPED flag, if present indicates that the region wraps around the sides (vertically and horizontally) of the landscape (e.g. a location x positions beyond the right-hand side of a raster will be mapped to x positions in from the left-hand side of the raster). If not present, the landscape does not wrap. Model Builder's Guide Chapter 9#Region Functions
DIRECTION
(Expr, Expr) angle in degrees between two location indices Model Builder's Guide Chapter 9#Continuous Functions (Miscellaneous)
==DISPLAY== Display on the screen the labelled Label: Expr values computed with the expressions listed. …. If no label is given, the expression must ENDFN be a variable, and this is used for the label. Model Builder's Guide Chapter 9#Output Expressions ==DISPLAY== Same as above, but only display if the DECISION Expr decision expression evaluates to TRUE Label: Expr The keyword DECISION can be replaced by …. a “?” ENDFN Model Builder's Guide Chapter 9#Output Expressions OUTPUT RECORD(OutputVar) Output to the record file of output variable the labelled values computed with the Label: Expr expressions listed. If no label is given, the …. Expression must be a variable and this is ENDFN used as label. Model Builder's Guide Chapter 9#Output Expressions OUTPUT RECORD(OutputVar) Same as above, but only output if the DECISION Expr decision expression evaluates to TRUE Label: Expr …. ENDFN
DISTANCE
(Expr, Expr) distance between two location indices (normally obtained using the Location variable). Thus, DISTANCE(loc1, loc2) is sqrt(sqr(loc1.x – loc2.x) + sqr(loc1.y – loc2.y)) Model Builder's Guide Chapter 9#Continuous Functions (Miscellaneous)
ELSE
expression evaluates to TRUE and the set of … sub-expressions after the ELSE otherwise. Note
ENDFN that “ELSE IF expr” forms can be strung togetherModel Builder's Guide Chapter 9#Control Expressions
EQUAL TRUE
(1) if the sub-expressions all evaluate to the same value and FALSE (0) otherwise Model Builder's Guide Chapter 9#Composite Functions
FLOOR
(Expr) largest integer smaller than the expression valueModel Builder's Guide Chapter 9#Continuous Functions (Arithmetic Functions)
GEOMETRIC MEAN
geometric mean of the sub-expressions (nth root of the product for n expressions)
Model Builder's Guide Chapter 9#Composite Functions
GREATER OR EQUAL
TRUE (1) if the sub-expression evaluations are all ordered according to the relation >=, and FALSE (0) otherwise Model Builder's Guide Chapter 9#Composite Functions
GREATER THAN
TRUE (1) if the sub-expression evaluations are all ordered according to the relation >, and FALSE (0) otherwise