You can work with coverage results collected using Simulink Test and results from another testing tool (which uses Simulink Coverage to measure test coverage). This should be done just using Simulink Coverage.
First, export the coverage results from Simulink Test using getCoverageResults. This will create a cvdata object.
You can combine the coverage results exported from Simulink Test with the coverage results from non-Simulink Test tests using the + operator, in addition to other operations (i.e., * for coverage intersection or – for coverage difference). For more than two simulations, you can perform these operations in a for loop.
One caveat is for results from a model reference hierarchy or model which calls external M functions. In that case, the non-Simulink Test results are going to be in a cv.cvdatagroup, but the exported results from Simulink Test will be array of cvdata. In this case, you will have to manually create cv.cvdatagroup from the latter.
In general, when working outside of Simulink Test, you need to ensure that they you are aggregating compatible items (e.g. not trying to sum cvdata for model1 with cvdata for model2).
