This dialog provides for modification of the geometrical arrangement of plot layers which are already present in the active graph window. You can add new layers or remove existing ones using the Number of layers control. Checking the Link X axes option makes all the X-axes interdependent, meaning that if you manually set abscissa scale limits on one plot layer, then the same limits will automatically be set on all other layers in the plot window.
You can specify the number of rows and columns that define a grid of plots. With the default settings, QtiPlot computes the size of the layers in the grid from the size of the graph window. If you check the Layer Canvas Size option, you can set the size of the drawing area for the layers. QtiPlot will then modify the size of the graph window to accommodate them. When the Fixed size box is checked, the size of the layers will be kept unchanged when you manually resize the graph window.
The controls in the two group boxes on the right, Alignment and Spacing, are used to set the alignment of the layers in the window and the margins between the layer borders and the graph window limits. The Spacing group includes an Align control with 2 options (Canvases and Layers) that control the meaning of the row and column spacing entries. If the Canvases alignment option is chosen, then the spacing fields define the distances between the axes of the layers. On the other hand, if the Layers alignment option is chosen, then the spacing fields define the distances between the borders of the layers.
Finally, it is also possible swap two layers using the Swap Layers controls. Simply select the Source and Destination layers and click the Swap button.
Once suitable choices have been made, clicking on either the Apply or OK buttons will arrange the layers to obtain the desired alignment of the vertical and horizontal axis.
Note that if modifications are later made to an aligned plots, then alignment of the different axes may be lost. Simply re-execute Arrange Layers... to again re-arrange the plot.