The xolotl
object has many properties that govern overarching simulation and environment characteristics. You can access any of these properties using dot notation (e.g. x.verbosity
).
Flags
All flags unless otherwise specified and default to 0 or false. Generally, flags are logicals (false or true) unless they have to interact with the underlying C++
code, in which case, they must be integers (0 or 1).
- The
verbosity
flag (0 to 99) toggles the amount of text printed to the console during compiling and simulation. It's handy for debugging. The verbosity flag goes up to 99. The higher the number, the more verbose the printed output. - The
closed_loop
flag (false or true) determines whether initial conditions should be reset before a new simulation. Ifclosed_loop
is true, successive simulations will use the current state of thexolotl
object (e.g. the end state of the previous simulation if you runintegrate
twice in a row). - The
approx_channels
flag (0 or 1) determines whether approximations to computing gating functions should be used. Look-up tables and approximations to the exponential function significantly increase computational speed, but decrease accuracy, especially at high temporal resolution in the data. - The
solver_order
flag takes the values 0 or 4. In the 0 case, standard solvers are used (exponential Euler). In the 4 case, a Runge-Kutta 4th order method is used instead. This method is slower but more accurate. - The
output_structure
flag (false or true) determines if outputs from theintegrate
function should be separate (false) or organized in a structure (true). The former is useful when you only want a few outputs or don't care about lots of variable names. The latter is useful when it's important to keep all the output data organized.
Numerical Properties
- The
dt
value stores the fixed time step (default ) for outputs from simulation. Note that this is not the same assim_dt
. This value determines the number of time steps in the output vectors. Ifdt
andsim_dt
differ, the simulation vector is interpolated before being output -- useful for running ultra-high definition simulations but not saving all that data. - In contrast,
sim_dt
is the actual fixed time step for the simulation (default ). -
t_end
is the simulation time (default ). -
The
temperature
property holds the in-silico preparation temperature (default 11 deg. C). This property only matters when using temperature-sensitive conductances or mechanisms. temperature_ref
holds the "default" temperature so that values can be used.- The
I_ext
property stores the current to be injected as a scalar, vector, or matrix. - The
V_clamp
property stores the voltage of clamped compartments as a matrix ofnSteps x nComps
wherenSteps
is the number of time-steps (x.t_end * x.dt
) andnComps
is the number of compartments in thexolotl
object tree.
Non-Numerical Properties
- The
manipulate_plot_func
property contains a cell of function handles which correspond to all plotting functions that are called when a property is changed while using themanipulate
functionality. It defaults to the built-inx.plot
function. - The
pref.m
file contains editable preferences for yourxolotl
installation.