Plot Page - Step Plots

The step plot properties Plot page contains the options to change the data file and axes; set data used in the plot; choose how step lines are drawn; create fit curves in the plot; and add a new plot to the graph. To view and edit step plot properties, click on the step plot in the plot window or Object Manager to select it. Then, click on the Plot tab in the Property Manager.

Change the step plot properties in the

Property Manager on the Plot tab.

Plot Type

The Plot type property displays the type of plot.

Worksheet

Click the existing data file path and file name next to Worksheet to select a different data file for the plot. Click on a currently open worksheet or click the Browse option to navigate to a worksheet that is not yet open. Select a different data file in the Open Worksheet dialog, and click the Open button to change the data. The plot automatically updates.

NOTE: The worksheet columns are retained after changing the worksheet. If any of the column options are blank after changing the Worksheet, click on the blank option and select the desired column. A blank next to column means that the column does not exist in the new worksheet.

Select the Data in rows option if your data file is formatted where each row includes one variable. When the Data in rows option is selected, all plot properties that require data values are specified by selecting a data row. This includes variables such as X and Y, data labels, worksheet ranges, etc. Properties that list column letters will update to list row numbers. When switching from plotting data in columns to plotting data in rows, Grapher may not be able to select the correct rows automatically. Verify the correct rows are selected.

The property descriptions below refer to data columns, but when Data in rows is selected the property lists will include rows.

Variables

Click on the column name next to the X variable or Y variable fields to change the columns used to create the plot. In the list that appears, select the new column. If the first worksheet row contains header information, the header information appears next to the column letter.

Aside from the columns containing data there are two other options, row number and sequence number. These options are available in the list that appears before the first column.

Selecting the Row number option plots the axis with the row numbers used in the Worksheet rows section. For example, if the first row is number two, the axis begins at a value of two.
The Sequence number option plots the data according to the total number of rows used. The sequence number always begins with the number one regardless of which rows are selected in the Worksheet rows group. Blank lines between rows are ignored when calculating the value. The sequence number increments by one when rows are adjacent or when rows are skipped.

When changing the X variable, Y variable, or Z variable to date/time data from numeric data, the Use date/time format option for the corresponding axis Tick Labels will automatically be checked to match the new data. When changing the X variable, Y variable, or Z variable to numeric data from date/time data, the Use date/time format option for the corresponding axis Tick Labels will automatically be unchecked to match the new data.

Step Lines

The Step line initial direction option determines how the step line is drawn between any two adjacent points. When Horizontal is selected the step lines are drawn so that they leave each data point parallel to the X axis. When Vertical is selected the step lines are drawn so that they leave each data point parallel to the Y axis. To change the Step line initial direction, click on the current option. Select the desired method of drawing the lines from the list. The plot automatically updates.

The plot on the left shows the step plot with the Step lines initial direction set to Horizontal. The plot on the right is set to

Vertical.

Missing Data

Rows containing text or blanks in the plotted columns are ignored and are not plotted on the graph. You can display the missing data as part of a continuous or discontinuous line using the Missing data options. Setting Missing data to Continuous plot connects the data line before and after the missing data. Setting Missing data to Discontinuous plot breaks the line at the missing data sections of the data set. Data filtered using a Data Filter are included as missing data. Missing data is not available for all plot types.


This plot has the Missing data option set to Discontinuous plot. The line breaks across the missing data point.	This plot has the Missing data option set to Continuous plot. The line continues and does not break across the missing data point.

Change Axes

Click on the axis name next to the X axis, or Y axis fields to change the axes used for the plot. Select another axis name from the list. Alternatively, click Select plots/axis to change the axis used by several plots on a graph at once.

See the Axis - Add to Graph page for information about how to add a new axis to the graph. Once the new axis is added to the graph, it will be available in the X axis or Y axis lists.

3D Settings

The 3D Settings section includes options for specifying the width, location, and number of lines in a 3D step plot.

Position

The Position option controls the location of the plot on the depth axis of the 3D plot. For example, 0 percent places the plot at the front of the graph, 100 percent places the plot at the back of the graph, and 50 percent places the plot in the middle of the graph.

Width

The Plot width controls the width of the plot. Plots can be 0.01 to 6 inches (0.025 and 15.24 cm) wide.

Line Frequency

Use the Line frequency field to control the cross lines along the plot width. The lines are usually drawn at each data point over the width of the plot, that is Line frequency is set to 1. When there are many points on the graph, the line color may overwrite most of the ribbon fill color. Use the Line frequency option to skip lines on the plot. For example, if Line frequency is set to 5, every fifth line is plotted on the plot. To remove all of the lines, set the Line frequency to a number greater than the total number of data points. Up to 10,000 points may be skipped between lines.

New Plot

Click the Create button next to the New plot command to create a new plot based on the current data file. A new plot is created using the same X variable as the selected plot. The Y variable changes to the next column in the worksheet that contains data. For example, if a selected step plot uses column A for the X variable and column B for the Y variable, clicking Create generates a new step plot with column A for the X variable and column C for the Y variable.

The new step plot is selected so you can change the new plot's properties. The line, fill, and/or symbol color automatically changes to a new color. The Plot palette and Don't use plot palette for line/scatter plots options on the Options dialog Plots page control the colors for plots added via the Create button in the Plot page.

Fit Curves

Click the Graph Tools | Add to Graph | Fit Curve command to add a fit curve to the graph. This adds a linear fit by default. Many fit types are available.