# SMS:Dataset Toolbox

From XMS Wiki

The *Dataset Toolbox* contains numerous tools for working with datasets. Once the options for the current tool have been set and a name for the resulting dataset has been specified, selecting the **Compute**, **Sample**, etc. button will create the new dataset. The name of the new dataset will appear in the list of datasets.

The *Dataset Toolbox* tools are organized as follows:

## Temporal

- Sample Time Steps
- Create a new dataset from sampled times of an existing dataset. If
**Interpolate times**is selected, linear interpolation will be used to determine the sampled times. If**Interpolate times**is not selected, the value from the nearest existing dataset time step will be used.

- Merge Datasets
- Starting SMS 11.2, two or more datasets can be merged together. The selected datasets must not have any overlapping time steps.

- Derivatives
- Create a new dataset of the change from one time step to the next, or the derivative from one time step to the next of an existing dataset. When computing a derivative, the time units must be specified. The the new dataset will output data in between the existing dataset time steps, resulting in one fewer time step than the original dataset.

## Math

- Compare Datasets
- Compare two datasets by subtracting the "Alternate" dataset from the "Base" dataset. User specified NULL values are assigned if the base or alternate dataset is inactive.

- Data Calculator
- For more information, see Data Calculator.

- Angle Convention
- Create a new dataset with a different angle convention from a scalar dataset containing directions in a given angle convention. With datasets for CMS-WAVE and STWAVE Cartesian grids, the angle can be converted to and from a shore normal convention.

## Spatial

- Geometry

Gradient- Creates a function that gives the gradient at each node. The gradient is calculated as the run divided by the rise.
Gradient Angle- Creates a function that gives the direction in degrees of the maximum gradient at each point.
Directional Derivative- Creates a vector function that gives the gradient (run/rise) in the x and y directions.

- Smoothing Datasets
- For more information, see Smooth Dataset.

- Grid Spacing
- Creates a function that gives the average distance between a node and its neighbors.

## Conversion

- Scalar to Vector
- Converts two scalar datasets to a single vector dataset. The specified scalar datasets can be either magnitude and direction or x and y components.
- Vector to Scalar
- Converts a single vector dataset into two scalar datasets. The resulting scalar datasets can be either magnitude and direction or x and y components.

## Coastal

- Local Wave Length and Celerity
- Creates two functions that calculate the celerity and wavelength at each node for any depths.
- .

- .

- Gravity Waves (Courant or Time Steps)
- Creates a function that gives the courant number for each node given the time step, or the gravity wave time step given the courant number.

- .

- .

- Advective (Courant or Time Steps)
- Advective requires a vector function as input and is disabled if no vector functions exist. The courant option creates a function that calculates the courant number given the time step and a velocity function. The time step option creates a function that calculates the time step given the courant number and a velocity function.

- .

- .

## Modification

- Map Activity
- This maps the activity array from one dataset to second dataset. This may be used to show only the values of interest on a particular dataset. This operation creates a new dataset.

- Filter
- This creates a new dataset based on specified criteria. The following options are available for filtering:
- < (less than)
- <= (less than or equal to)
- > (greater than)
- >= (greater than or equal to)
- equal
- not equal
- null
- not null

- If the value passes the specified filter, the following can be assigned:
- original (no change)
- specify (a user specified value)
- null (the dataset null value)
- true (1.0)
- false (0.0)
- time – The first time the condition was met. Time can be specified in seconds, minutes, hours or days, and includes fractional values (such as 3.27 hours).

- In addition, if the value passes none of the criteria, a default value can be assigned (see available options above).

- The filtering is applied in the order specified. This means as soon as the new dataset passes a test, it will not be filtered by subsequent tests.

## Related Links

SMS – Surface-water Modeling System | ||
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Modules: | 1D Grid • Cartesian Grid • Curvilinear Grid • GIS • Map • Mesh • Particle • Quadtree • Raster • Scatter | |

General Models: | FVCOM • Generic • PTM • TUFLOW FV | |

Coastal Models: | ADCIRC • BOUSS-2D • CGWAVE • CMS-Flow • CMS-Wave • GenCade • STWAVE • WAM | |

Riverine/Estuarine Models: | ADH • FESWMS • HEC-RAS • HYDRO AS-2D • RMA2 • RMA4 • SRH-2D • Steering • TUFLOW | |

Aquaveo • SMS Tutorials • SMS Workflows |