FME2009函数速查手册.doc

-29-29FME2009函数速查手册FME Workbench Transformers Quick-Reference BookletThis booklet contains a high-level summary of each transformers functionality. For detailed information, please visit or select FME Transformers from the Workbench Help menu.What is a Transformer?A transformer is an FME Workbench object that carries out the restructuring of features. FME contains over 300 different transformers to carry out different types of restructuring. In the Workbench interface, transformers are stored in the Transformer Gallery, and grouped in categories applicable to their associated functionality.Common Elements Used in Transformer Parameter DialogsEvery transformer has a Properties button on the right of the transformer.Properties buttonWhen you click the Properties button, most transformers display an Edit Parameters dialog. The content of this dialog depends on the transformer, and sometimes even on connections to the transformer. Most transformers have some common user interface elements, however, and those are described here.The Properties button at the top-right of the transformer is color-coded to show the status of the settings.If the Properties button is the same color as the transformer, you can use the transformer with its existing parameters.A yellow Properties button indicates that the transformer contains default settings, but you have not yet accepted them. You can use the transformer in this state, but the workspace results may be unpredictable.A red Properties button means that there is at least one parameter for which FME cannot supply a default value. You must provide a value in the required field(s) before the transformer can be used.When you click a Properties button, the Edit Parameters dialog that appears will usually have some of the common elements shown in this example.You can edit the default transformer name.Required fields are highlighted. If this field is not filled in, the OK button at the bottom of the dialog is disabled.Click this Help button to open the FME Workbench Transformer help topic.Click OK to accept changes and close the dialog. Note that this button is disabled if required fields have not been populated.The Defaults menu allows you to replace FME defaults for this transformer with your own parameter defaults. You can always reset the dialog to FME defaults.(一) 3DTransformerBrief Description功能简介一3DThese transformers create and modify three-dimensional surface and solid geometries.1CSGBuilderCreates Constructive Solid Geometry (CSG) from pairs of solid geometry features.2CSGEvaluatorReplaces the geometry of a feature that has CSG.3ExtruderCreates long, surface or solid geometries with a fixed cross-sectional profile taken from the original geometry of the feature.4FaceReplacerReplaces the geometry of a feature from donut or polygon to face.(二) Calculators二CalculatorsThese transformers calculate a value and supply it to a new attribute on a feature.1AreaCalculatorCalculates the area of a polygonal feature and adds it as a new attribute.2AttributeRounderRounds off an attribute to the specified number of decimal places.3BaseConverterConverts an attributes value from one numeric system (base) to another, putting the resulting value in a new attribute.4BoundsExtractorExtracts the minimum and maximum values of the features coordinates into new attributes.5CircularityCalculatorCalculates the circularity of an area feature, which indicates how elongated the feature is.6CoordinateConcatenatorRetrieves the value of all of the features coordinates into an attribute, separated by the delimiter characters.7CoordinateCounterStores the number of a features coordinates into an attribute. For multi-part features (aggregates), this is the sum of all coordinates in all parts of the feature.8CoordinateFetcherRetrieves the value of the x, y, and z coordinates at the specified index into attributes.9CounterAdds an attribute holding the next integer in a sequence.10CRCCalculatorCalculates a Cyclic Redundancy Check (CRC) value as directed for a feature and places at value into the specified attribute.11DateFormatterReformats and replaces date or time strings (in the Date Attributes) into a new date format.The source string can be in almost any date and/or time format. Some valid examples include:20031209 15:05 December 9, 2003 09 December 03, 15:05 3:05pm12DecimalDegreesCalculatorCalculates a decimal degree value from separate degrees, minutes, and seconds (DMS) values, stored in attributes.13DEMDistanceCalculatorCreates a DEM after the reference DEM and is then output.14DimensionExtractorReturns the dimension of the feature as a new attribute.15DMSCalculatorCalculates DMS from a decimal degrees value stored in an attribute.16ElevationExtractorExtracts the elevation of the first coordinate and assigns it to the named attribute.17EnvironmentVariableRetrieverRetrieves the specified Environment Variable and puts it into the specified attribute.18ExpressionEvaluatorEvaluates an arithmetic expression and returns the result in a new attribute.19HoleCounterAdds a new attribute whose value is the number of holes in the feature.20InsidePointExtractorGenerates a point guaranteed to be inside the area feature and adds the coordinates of this point to the feature as attributes.21LengthCalculatorCalculates the length of a feature and adds it as a new attribute.22ModuloCounterAdds an attribute holding the next integer in a sequence and restarts the count at 0 whenever the sequence reaches a maximum defined value.23OrientationExtractorDetermines the features orientation and returns it in the specified Orientation Attribute.24RandomNumberGeneratorGenerates a random number with a set number of decimal places in the inclusive range specified.25ReprojectAngleCalculatorCalculates the reprojected angle of a line, which is useful for calculating reprojected text angles.26ReprojectLengthCalculatorCalculates the reprojected length of a line, which is useful for calculating reprojected text heights.27SpatialRelatorDetermines topological (spatial) relationships between sets of features.28StatisticsCalculatorCalculates statistics based on a designated attribute of the incoming features.(三) Collectors三CollectorsThese transformers operate on collections of features at the same time. The collection of features may be replaced by new features based upon them, have their attributes or geometries merged, or have their orders altered.12DGridReplacerReplaces the input features with a grid of two-dimensional point features that have the specified spacing and which cover (at least) the bounding box area of all features that enter the transformer.2AggregatorCombines feature geometries into aggregates. One aggregate feature is output for each unique combination of values of the attributes specified in the GROUP BY.3AttributeAccumulatorCombines feature attributes.4BoundingBoxAccumulatorCreates bounding boxes for groups of features. One bounding box feature is output for each unique combination of values of the attributes specified in the GROUP BY.5CommonSegmentFinderTests to see which of the CANDIDATE features have even one segment in common with any BASE feature.6ConvexHullAccumulatorCreates convex hulls for groups of features.7DeaggregatorDecomposes an aggregate feature into its components.8FeatureHolderStores incoming features until they have all arrived and then releases them in their original order.9FeatureMergerMerges the attributes of one feature onto another feature. 10NeighborFinderFinds the closest CANDIDATE feature within some maximum distance of at each BASE feature.11NeighborhoodAggregatorCreates aggregates of features based on their proximity to each other.12NeighborPairFinderFinds the closest two CANDIDATE features within some maximum distance of each BASE feature and some minimum separation in heading between the CANDIDATEs and the BASE.13SorterSorts features by an attributes value.(四) Database四DatabaseThese transformers allow interaction with external databases. Data can be extracted from databases and merged into the feature stream, or merged onto features. Arbitrary SQL statements can also be executed.1ArcSDEQuerierPerforms queries on an ArcSDE spatial database. The queries can have both a spatial and a nonspatial component.2JoinerQueries a database to retrieve attributes associated with a feature.3OracleQuerierPerforms spatial queries against an Oracle Spatial database.4SchemaMapperMaps the schema (attributes and feature types) of features based on a schema mapping table.5SQLExecutorRuns an arbitrary SQL statement against a database.(五) Filters五FiltersThese transformers perform tests on feature geometry and/or attributes, and allow the feature to be routed to different destinations depending on the outcome of the test.1AggregateFilterRoutes features differently depending on whether their geometry consists of an aggregate of several primitive geometries or a simple, single piece geometry.2AttributeFilterRoutes features to different output ports depending on the value of an attribute.3ChangeDetectorDetects changes between two sets of input features.4DuplicateRemoverRemoves duplicate features based on the value of a key attribute.5FeatureTypeFilterSeparates the features routed to it into their original feature types, if possible.6GeometryFilterRoutes a feature based on its geometry type.7GeometryOGCValidatorEvaluates the simplicity or validity of a geometry feature and routes the feature according to the outcome of the tests.8MatcherDetects features that are matches of each other.9SamplerDiscards input features, preserving only every th feature.10SpatialFilterFilters features based on spatial relationships.11TesterEvaluates one or more FME-style tests on a feature, and routes the feature according to the outcome of the tests.(六) Geometric Operators六Geometric OperatorsThese transformers operate on the geometry of individual features or groups of features.1AffineWarperPerforms warping operations on the spatial coordinates of features. It is used to adjust a set of observed features so they more closely match some set of reference features.2AnchoredSnapperSnaps endpoints of features entering through the CANDIDATE port to endpoints of features entering through the ANCHOR port. ANCHOR features are not output.3AreaBuilderForms area features from lines and optionally cuts out any resulting holes from their containers. This one transformer performs the same functions as the combined PolygonBuilder and DonutBuilder.4AreaOnAreaOverlayerPerforms an area-on-area overlay. All input areas are intersected against each other, and resulting area features are created and output.5ClipperPerforms a geometric clipping operation.6DissolverDissolves area features by removing common boundaries to create larger areas.7DonutBridgeBuilderBuilds connections between donut holes with the outer boundary of a donut, resulting in a polygon-equivalent representation of the input donut.8DonutBuilderCuts holes in polygonal features by making polygons completely enclosed in other polygons into holes of the containing polygon.9DonutHoleExtractorSplits an area feature that has holes into its component rings.10IntersectorComputes intersections between all input features, and breaks lines and polygons wherever an intersection occurs.11LabellerInterpolates labels along a linear or polygonal feature.12LineJoinerTakes non-intersecting lines and connects them into longer lines whenever doing so does not remove a significant node.13LineOnAreaOverlayerPerforms a line-on-area overlay.14LineOnLineOverlayerPerforms a line-on-line overlay.15MRFCleaner (2D and 3D)Takes features as input and processes them based on the specified modules, tolerance, dangle factor, filter factor, and specific attribute data.16NeighborColorSetterAssigns colors to areas in a coverage such that adjacent areas are colored differently and the total number of colors used is kept small.17PathBuilderConnects input linear features (arcs and lines) in the order they enter, forming path features.18PointConnectorConnects input point features in the order they enter, forming linear or polygonal features.19PointOnAreaOverlayerEach point receives the attributes of the area(s) it is contained in, and each containing area receives the attributes of each point it contains.20PointOnLineOverlayerEach input line is split at its closest place to any point within the specified point tolerance.21PointOnPointOverlayerEach input point has the attributes from any other point within the Point Tolerance distance merged onto it.22PolygonBuilderForms polygons from lines.23RubberSheeterPerforms warping operations on the spatial coordinates of features.24SelfIntersectorChecks each feature and removes self-intersections.25SnapperSnaps end points of lines together if they are within the distance of each other.26SpikeRemoverCleans up feature geometries by removing spikes in two dimensions.27TilerChops the input features into a series of tiles.28TopologyBuilderComputes topology on input point, line, and/or area features.29TriangulatorBreaks an input geometry into triangular units.(七) Infrastructure七InfrastructureThese transformers provide interaction with the underlying FME translation engine facilities. These include functionality to log features, set feature colors, create individual features and grids of features from nothing, and invoke the FME Viewer on features flowing by.12DGridCreatorCreates a grid of two-dimensional point features, at the origin and uses the offsets specified.2AreaFillColorSetterSets the fill color for the features area. Formats that support color will then render the interior feature in the set color.3AttributeCopierCopies existing attributes to new attributes with the specified names.4AttributeCreatorAdds a number of attributes to the feature and supplies it with constant values.5AttributeDereferencerCopies the value of the attribute whose name is held in the source attribute to a newly created attribute.6AttributeExposerExposes a series of attributes.7AttributeFileReaderReads the contents of a file and stores them as the value for the specified attribute.8AttributeFileWriterWrites the contents of the specified attribute to a file.9AttributeRenamerRenames a set of attributes.10AttributeSetterSets an existing attribute to a constant value.11ClonerMakes copies of the features input and outputs all copies through its single output port.12CreatorCreates features using the parameters supplied and sends them into the workspace for processing.13FeatureTypeExtractorAdds an attribute containing the original feature type of a feature.14LoggerLogs each feature to the translation log.15ParameterFetcherAdds an attribute to the feature and supplies it the value of a previously published parameter.16PenColorSetterSets the pen color of the feature.17PlayerRetrieves features stored in an FME Feature Store file and outputs them into the workspace.18PythonCallerProcesses FME features using a Python object referenced by the symbol name parameter.19PythonCreatorGenerates FME features using a Python object referenced by the symbol name parameter. The handler object can be a Python function, a Python class, or any Python object that understands the FME Factory protocol.20RandomColorSetterSets a random color for each incoming feature.21RecorderSaves a copy of all features that enter to a disk file.22SummaryReporterWrites a summary report of features that enter to a disk file. Features are sorted before they are summarized.The summary report is a human-readable text file that can be read by any text editor. This summary report can be used to compare and quickly find differences between sets of features.23SystemCallerRuns a program and waits for it to exit before continuing the translation.24TCLCallerRuns a Tool Command Language (Tcl) command and assigns its return value to an attribute.25TerminatorCauses the translation to end and prints the specified message in the translation log as the reason for the termination.26TransporterReceiverProvides a mechanism to receive features from another FME workspace running in a different process. Although the processes may be located on the same machine or on a different machine, one of the most advantageous uses will be to partition large workspaces into smaller components that each have their own address space. Used in conjunction with the TransporterSender.27TransporterSenderProvides a mechanism to send features from another FME workspace running in a different process. Although the processes may be located on the same machine or on a different machine, one of the most advantageous uses will be to partition large workspaces into smaller components that each have their own address space. Used in conjunction with the TransporterReceiver.28VariableRetrieverReplaces the GlobalVariableRetriever. The Variable Scope pa