# STREAMLINE

Streamlines are massless particles moving along a path with a velocity tangent to the streamline at every point.

## Syntax

STREAMLINE(“name”) { parameters}

## Qualifier

User-given name

## Parameters

- display_seeds (boolean)
- When activated, the seed locations will be displayed as spheres.
- seed_type (enum)
- Method of identifying seed locations
- normal_direction (enum)
- Used when seed_type=rectangular
- x_center (real)
- x-coordinate of centerpoint of rectangle. Used when seed_type=rectangular.
- y_center (real)
- y-coordinate of centerpoint of rectangle. Used when seed_type=rectangular.
- z_center (real)
- z-coordinate of centerpoint of rectangle. Used when seed_type=rectangular.
- x_length (real)
- Length of rectangle in the x direction. Used when seed_type=rectangular.
- y_length (real)
- Length of rectangle in the y direction. Used when seed_type=rectangular.
- z_length (real)
- Length of rectangle in the z direction. Used when seed_type=rectangular.
- x_seeds (integer)
- Number of seeds equally spaced along the rectangle in the x direction. Used when seed_type=rectangular.
- y_seeds (integer)
- Number of seeds equally spaced along the rectangle in the y direction. Used when seed_type=rectangular.
- z_seeds (integer)
- Number of seeds equally spaced along the rectangle in the z direction. Used when seed_type=rectangular.
- x_1 (real)
- x location of first seed of rake. Used with seed_type = rake.
- y_1 (real)
- y location of first seed of rake. Used with seed_type = rake.
- z_1 (real)
- z location of first seed of rake. Used with seed_type = rake.
- x_2 (real)
- x location of second seed of rake. Used with seed_type = rake.
- y_2 (real)
- y location of second seed of rake. Used with seed_type = rake.
- z_2 (real)
- z location of second seed of rake. Used with seed_type = rake.
- num_seeds (integer)
- Number of seeds to place between two specified points for rake
- name (string)
- User-given name of the command. The instance of a given command is referenced using this parameter.
- color_type (enum)
- Method used to set the display color
- constant_color (enum)
- Display the streamline as a constant color
- num_contours (integer)
- Number of contour lines to be displayed in legend
- contour_function (string)
- Scalar quantity to be displayed on streamline (pressure, velocity, and so on)
- vector_function (string)
- Vector field to define the streamline computation (velocity, time_avg_velocity, velocity_xz, time_avg_velocity_xz)
- line_thickness (enum)
- Thickness of lines for mesh display and feature line display
- legend_display (boolean)
- Flag to toggle on or off the visibility of the legend
- legend_min (real)
- Minimum value in legend
- legend_max (real)
- Maximum value in legend
- legend_location (enum)
- Location of the legend on the image
- legend_use_local (enum)
- Boolean to control the local legend range. If active, will set for local entity range.
- colormap_name (enum)
- Colormap name to use for displaying the scalar function values

## Example

```
STREAMLINE("upstream rake"){
calculation_direction = forward
time_limit = "_none"
display_seeds = off
seed_type = rake
normal_direction = x
x_1 = (xMax-xMin)*.2 + xMin
y_1 = yMax*.99
z_1 = (zMax-zMin)/2.0 + zMin
x_2 = (xMax-xMin)*.2 + xMin
y_2 = yMin*.99
z_2 = (zMax-zMin)/2.0 + zMin
num_seeds = nSeeds**2.0
line_thickness = thin
color_type = contour
contour_function = "velocity_magnitude"
legend_display = on
vector_function = "velocity"
legend_use_local = off
legend_min = .6*meanVel
legend_max = 2.5*meanVel}
```