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2D Overlay

2D Overlay

Overlaying multiple 2D spectra

It is possible to overlay up to 4 contour plots, displayed in different colors. To facilitate this, wxNUTS allows up to 4 data sets to be loaded simultaneously, referred to as data sets A, B, C and D. Below, HSQC and HMBC spectra of codeine are overlaid.

The 2D Overlay mode can be turned on and off with the command 2Doverlay. The command syntax is:

2Doverlay – toggles the overlay mode on and off
2Doverlay on
2Doverlay off
2Doverlay help or 2Doverlay ? – displays a brief description of the command syntax

Before multiple contour plots can be displayed in overlay mode, each must be opened. Commands that can be used to open each file are:

GA – open a file to be designated file A
GB – open a file to be designated file B
Open A (or B or C or D) – open a file to be designated file A (or B or C or D)

Each data set can be viewed individually using one of the following commands:

AA – display file A
BB – display file B
CC – display file C
DD – display file D

A notation appears on the status bar to indicate which spectrum is currently displayed: Base-A, Base-B, etc. The text at the top of the window displays the file name and the Comment line.

A previously loaded data set can be removed with the appropriate one of the following commands:

AA clear
BB clear
CC clear
DD clear

When 2D overlay is turned on and a contour (or intensity) plot is displayed, all currently open data sets are drawn. The user cannot select a subset of data to be displayed (see comments regarding gain, below). There must always be a data set A.

The different data sets can be scaled as needed, by entering Gain multipliers, with the following commands:


Typing one of these commands with no command line argument displays the value of all 4 gains. The gain can be changed by typing, for example, GainA 2, which would increase the gain of data set A by a factor of 2. Note that a quick way to display a subset of the currently open data sets is to set the corresponding gain very low.

By default, when in 2D overlay mode, the 4 contour plots are drawn with the following colors:

A – black
B – red
C – green
D – blue

It is possible to set different colors for each of the 4 data sets, but positive and negative levels will always be the same for a given data set. The command syntax to set the color is:

2Doverlay N x y z

where N is the data set (A, B, C or D) and x, y and z are values for Red, Green and Blue. Each of these values is a number between 0 and 255. For example, 0 0 0 is black, 255 0 0 is red, 255 255 0 is yellow. You can download a nifty little Windows utility program that lets you adjust the 3 values and see the resulting color.

Last updated: 3/25/09