**Guide Section: Diagramming **

**EASAP Tree:**

**USER INTERFACE** → **DIAGRAM LIST** → **2D GRAPH**

**OUTPUT** → **REPORT** → **2D GRAPH**

**CONTOUR DATA** specifies contour data to be plotted on a **2D GRAPH**.

The contour data consists of the **X Values:** and **Y Values:** that form a rectangular space, and the **Data Values:** to be contoured within the rectangular space. These three parameters are each defined by **LIST**'s. Unlike in **LINE DATA**, the size of the **LIST**'s here should NOT all be the same size, **X Values:** should only have one row of values which specify the number of columns in the data, **n** and the plot domain for that axis. **Y Values:** should only have one column of values which specify the number of rows, **m** and the range for that axis.

Finally, the **LIST** in the **Data Values:** parameter should contain **n** times **m** number of values, and the order of the data should be structured such that the rows of data at each X value are completed one after the other, starting with the row at the first Y value.

This ordering of the contour data is illustrated by the line running from the bottom to the top of the graph shown below.

With **CONTOUR DATA** there are three basic contour styles that can be used alone or in combination:

- Line contours along constant data values
- Color filled rectangles for each data point
- Color fill between contours of constant data values.

More than one **CONTOUR DATA** may be used per **2D GRAPH**. However, you should take care to differentiate the different data values. For example, use line contours for one set of data and filled contours for another.

CONTOUR DATA | |
---|---|

Essential Parameters: | |

X Values: | LIST reference or literal list containing horizontal coordinate (abscissa) values (length→n, values span plot domain) |

Y Values: | LIST reference or literal list containing vertical coordinate (ordinate) values (length→m, values span plot range) |

Data Values: | LIST reference or literal list containing data to be contoured (length→n x m) |

Optional Parameters: | |

Type: | Select data type to plot (default→LINEAR, LOGARITHMIC ) |

Contour Style: | Select contour style. (default→LINE, POINTS, POINTS_LINE, FILL, FILL_LINE) |

Contour Values: | Comma-separated list of contour values to be plotted |

Number of Contours: | Number of contours to be plotted. default→4 |

Refinement Factor: | Factor used on sparse data to form smoother contours |

Label: | Label for data used in a Child LEGEND |

We may set a value for either the **Contour Values:** or the **Number of Contours:** parameter, but not both. An error message will be displayed if both of these two parameters are set.

For example to generate one quadrant of a spherical shell over a 4 x 3 grid of points set:

**xVals**→[0, 1, 2, 3]**yVals**→[0, 1, 2]

- Create a
**CONTOUR DATA myPlot** - Set
**myPlot→X Values: xVals** - Set
**myPlot→Y Values: yVals**

- Create a
**CONCATENATE****xlist**with**Lists: xVals**,**xVals**,**xVals** - Create a
**LIST DOR ylist**with**Value:**[0, 0, 0, 0, 1, 1, 1, 1, 2, 2, 2, 2] - Create a
**REPEATED COMPUTE dataVals**- Set:
**dataVals→Value:**sqrt(16 -**ylist*****ylist**-**xlist*****xlist**)

- Set
**myPlot→Data Values: dataVals**

**CONTOUR DATA** plot with **Number of Contours:**15 and **Contour Style:** FILL_LINE and LINE, respectively: