| 14 | | For the first case, to visualize the results of the MMTK normal modes calculation example, we can create a Chimera trajectory of the molecule. The trajectory represents a single normal mode and has four sequential steps (equilibrium position, positive extreme, equilibrium position, negative extreme). When played, the trajectory will appear to oscillate between the two extremes. For this example, we need two source files: [attachment:showNormalModes.py showNormalModes.py] and [attachment:NormalModesTable.py NormalModesTable.py]. [attachment:showNormalModes.py showNormalModes.py] consists of the MMTK sample normal mode code, followed by the lines: |
| | 14 | == Visualizing Normal Modes == |
| | 15 | |
| | 16 | To visualize the results of the MMTK normal modes calculation example, we can create a Chimera trajectory of the molecule. The trajectory represents a single normal mode and has four sequential steps (equilibrium position, positive extreme, equilibrium position, negative extreme). When played, the trajectory will appear to oscillate between the two extremes. For this example, we need two source files: [attachment:showNormalModes.py showNormalModes.py] and [attachment:NormalModesTable.py NormalModesTable.py]. [attachment:showNormalModes.py showNormalModes.py] consists of the MMTK sample normal mode code, followed by the lines: |
| 23 | | For the second case, to follow the progress of a minimization run, we can create a Chimera molecule from the MMTK universe and update its atomic coordinates as minimization progresses. To keep Chimera interactive, we can run the minimization in the background, and poll for atom coordinates changes every few display frames. The example code is in [attachment:followMinimization.py followMinimization.py], which contains a mix of MMTK and Chimera code. |
| | 25 | == Monitoring Molecular Dynamics == |
| | 26 | |
| | 27 | To follow the progress of a molecular dynamics run, we can create a Chimera molecule from the MMTK universe and update its atomic coordinates as simulation progresses. To keep Chimera interactive, we can run the simulation in the background, and poll for atom coordinates changes every few display frames. The example code is in [attachment:followMD.py followMD.py], which contains a mix of MMTK and Chimera code. |
| | 28 | |
| | 29 | A more elaborate example, [attachment:plotMD.py plotMD.py], extends the previous example to include a plot of the system potential energy along with updating atomic coordinates. The additional creates a '''matplotlib''' plot, and registers a callback function that is invoked whenever Chimera atomic coordinates are updated. The arguments to the callback are (1) the MMTK universe, (2) a mapping from MMTK atoms to Chimera atoms, and (3) an MMTK state (which is '''None''' when the callback is invoked after the simulation ends). The execution of plotMD.py is shown in [attachment:plotMD.mp4 plotMD.mp4]. |
| | 30 | |
| | 31 | == Caveats == |