# 6.12.8 Surface with Symbols and Droplines

## Summary

Origin supports transparency in most graph types. This feature permits the visibility of parts of a graph that would otherwise be obscured by overlapping plots. In this tutorial, we will add a fitted surface to a scatter plot, set transparency to make data points "behind" the surface visible, and add drop lines and error bars for data points.

Minimum Origin Version Required: 8.5 SR0

## What you will learn

• Create a 3D scatter plot from worksheet data and add a color fill surface to it.
• Draw drop lines or error bars for data points.
• Set surface transparency.

## Steps

### Create a surface graph with symbols and droplines

This tutorial is associated with <Origin EXE Folder>\Samples\Tutorial Data.opj.

1. Open the Tutorial Data.opj and browse to the folder Surface with symbols and droplines.
2. Active the worksheet XYZRandomGauA, highlight the XYZ to plot a 3D scatter by selecting Plot > 3D : 3D Scatter from the main menu.
3. Now we will add a 3D Color Fill Surface plot to this 3D scatter graph. In the top left corner of the graph window, double-click the layer 1 icon to open the Layer Contents dialog.
4. In the Layer Contents dialog box, select Matrices in Folder from the dropdown menu in the upper left. In the left panel, select MBook 3, Click the triangle button next to A and select 3D - Surface.
Click to add it to the right panel.
5. Click OK button to apply the change and close the Layer Contents dialog. Double-click the graph to open the Plot Details dialog box. In the left panel of this dialog, expand all items and select Original (or choose Plot from the Format menu). In the right panel, on the Symbol page set Size as 9 and Color as Olive from Individual Color fly-out menu and click Apply.
6. In the left panel, select the surface plot, and then go to the Fill tab in the right panel, change the Fill piece by piece as Red. Set Transparency to 60 and click Apply.
7. Go to the Mesh tab, set the Line Width as 1 and Set Total Number of Majors as X=9 and Y=9, and Major Line Color as Black and click Apply.
8. Now we will draw the drop lines. In the left panel, select the scatter plot (Original). In the right panel, select the Drop Lines tab. Select the Parallel to Z Axis check box, change the drop line Width to 2 and set the Drop to to Surface.
9. Click OK to close the dialog and delete the legend. Your final graph should look like this:

### Create a surface with symbols and error bar

1. Follow steps 1 through 8 above and click OK to create a 3D surface graph with a scatter plot.
2. Add a new column in the worksheet "XYZRandomGauA". Select the column and right-click. In the Fill Column with context menu, click Uniform Random Numbers.
3. Double click on the newly created graph to open the Plot Details dialog. Expand the node to select the plot (Original) in the left panel. On the Error Bar tab, select the Enable check box, and select Col(D) from the Error Data dropdown menu.
4. Click OK to close the dialog and delete the legend. Your final graph should look like this: