LL – Line List
This is a subroutine within 2D display that allows vertical and horizontal lines to be drawn on the spectrum to aid in spectral interpretation. The lines are "attached" to the spectrum by ppm value, so the lines remain in place as the spectrum is zoomed in/out.
Lines can be placed on a 2D plot without entering the subroutine, but the subroutine allows the appearance of the line to be edited.
To add a line to a 2D plot, first press and hold the left mouse button to display a large red cross-hair cursor (referred to as the "target" cursor). While the target cursor is displayed, typing a V places a vertical line at the current target position, and typing an H places a horizontal line at the target position. L clears the last entered line and C clears all entered lines.
When the command ppmlines or LL is given from the 2D base level, the Edit Line List routine is entered. If the cursor is moved over a line, it will blink and that line becomes the selected as the current line. At this position, a right click or the key E will enter the mode to edit the properties of the current line. Typing the D key will delete the current line and typing C will clear all current lines. To add more lines while in the LL subroutine, holding down the mouse button is optional, but the target cursor is helpful in choosing the desired line position. Place the cursor at the desired position, and type either V for a vertical line or H for a horizontal line.
On entering the LL routine, note that the status bar shows Edit PPM Line List and the menus have changed. As with all subroutines, typing <ENTER> or choosing Exit from the File menu will exit the LL subroutine.
Use the "target" cursor to display a large cross-hair, to aid in positioning the line.
Typing H draws a horizontal line at the cursor position.
Selecting the line (by moving the mouse cursor across the line, causing the line to blink) and typing E displays a dialog box that allows the line’s width, style and color to be set. Color is set using RGB values or by clicking the GUI Color button to select color.
The lines remain after exiting the LL routine, and continue to be displayed at the same ppm value even if the displayed region is changed.
As of 12/8/06, new commands have been added that work with the data table and the Line List feature for contour plots. Highlight a cell containing a chemical shift, and type either HL or VL. A horizontal or vertical line is drawn on the contour plot at the corresponding chemical shift.
Last updated: 12/8/06