Automatic Integration and Automatic Scale Fragmentation
Manual integration couldn't be simpler but, if you prefer, iNMR can decide the integral regions for you. There are two gradations: you can choose the default behavior or you can experiment with modulating the algorithm. If you don't care about the details, press Cmd+Alt+I (shortcut for “View/Integrate Now”). If you don't press the “Alt” key you'll reach the dialog. At this point you can close the dialog (either accepting or refusing the integration) or you can play with the sliders. Each slider corresponds to a filter.
Automatic integration is performed by applying a chain of filters. Each filter can reduce the number of integrals. The very first filters are hard-coded into the program and you can't do nothing about them. The last three filters are user-adjustable. Any pre-existing integral region remains unaffected.
- minimal width (points)
- If an integral region contains less points than this value, it is filtered out. When the value is = 1 point, this filter has no effect.
- merging distance (ppm)
- iNMR adds more space to both sides of each integral. If two integrals are very near to each other, they will be fused. When the value of this filter is = 0 ppm, it has no effect.
- maximum allowed ratio
- This value corresponds to the normalized intensity of the highest integral. All integrals whose intensity is less than one are eliminated. The highest the value, the more integrals are created. When you set this value = 5, then the weak integrals (less than 20% of the tallest one) are eliminated. You can set values higher than 200 when you run this command from the console, yet you will normally prefer smaller values.
Negative integrals are never created automatically.
The same regions, instead of being integrated, can be used for multiple expansions (what you normally achieve with the cutter tool). You have a switch at the bottom of the dialog to choose between integration and cutting.