When you open a new simulation file, it will start out in Layout mode.
Once the simulation has been run, it will be in Analysis mode.
Layout mode is the state of the file while the simulation is being set up and simulation
objects are being modified, and Analysis mode is the state of the file after running the
simulation when the simulation data is available to collect and analyze.
Once the simulation has been run and the file is in Analysis mode, it is no longer possible
to modify the simulation setup properties such as the size or material of an object,
or the placement of a monitor since the simulation results correspond to the current setup, and
modifying the structures or monitors would cause the setup and results to be inconsistent
or out-of-sync with each other.
In Analysis mode, it is only possible to modify properties that would not cause the simulation
results to need to be updated.
For example in analysis groups, which we'll cover in a following unit, the analysis scripts
used to perform post-processing of monitor data does not affect monitor results, so they
can be changed.
Because monitors contain data after running the simulation, when you save the simulation
file in Analysis mode, the resulting file size will be larger compared to if you saved
the file in Layout mode.
In Analysis mode, it is also possible to calculate additional results based on monitor data in
post-processing such as calculating the far field projections from near field frequency-domain
field monitors, or calculating analysis groups results, and this additional data is also
saved in the file so it will also add to the simulation file size.
You can switch from Analysis mode back to Layout mode by using the "Switch to layout"
button in the simulation toolbar.
This button toggles between the "Run" button while in Layout mode, and the "Switch to layout"
button while in Analysis mode.
Or, you can edit an object and switch to layout from the edit window button.
Once you switch from Analysis mode to Layout mode, all monitor data from running the simulation
will be lost.
However, as long as you don't re-save the file, when you open a new instance of the
file, the file will still be in Analysis mode with the monitor data.
Once you save the file while in Layout mode, you will not be able to recover the data from
running the simulation and you would need to re-run the simulation to get results again.
If you want to preserve the data, you can export the data before switching back to Layout
mode and then re-load the data later, and data export options will be covered in detail in
a following unit.
In the next unit we'll look at the design workflow for simulations.