FAST: Vectors

Note: FAST cannot display vector fields from unstructured data.

Read in a grid file, and a vector function file, start the "Surfer" module and position the grid as desired.

To display a vector field, from the "Surfer" module, pull the "Render" menu down to either "Plain Vectors" or to "Normalized Vectors". A vector field will appear. Note: The vectors will appear as line segments. To add arrow heads to them, pull the "Attributes" menu down to "Arrowed Vector Tips". Unfortunately, you cannot modify the vector tips . You can, however, change the size of the vectors, the color of the vectors display fewer vectors.

To change the size (scale) of the vector, pull the "Panels" menu down to "Vector Scale ...", and enter a new scale factor.

To change the color of the vectors, pull the "Panels" menu down to "Colors...", click on "Vectors" and use the sliders to adjust the colors.

To display fewer vectors, modify the "I Inc", "J Inc" and/or "K Inc" at the bottom of the "Surfer". This panel is as follows.

Unless otherwise stated, vectors at each point are shown. Here is an example.

In this example, the vectors run together. To correct this we can show fewer vectors. In the following example, we can see every fourth vector along each circle, and we see every other circle.

Vectors usually need more information. They can be combined with meshes, surfaces and contours to visualize the data. Here is an example of a vector field displayed along with the mesh.

• Click on the "Copy Object" button,
• Click on the object "surfer#2".
• Use the "Render" and "Attributes" menus and such to create the vector field for "surfer#2".

The above figure actually uses three objects: Every fourth vector of the smallest circle is shown, while every other vector of the other circles is displayed.