Field Examples

Complex Waveform Field with Initializer

local ctx = sim.sim_create()
sim.sim_set_timestep(ctx, 0.01)

local wave = sim.sim_add_field(ctx, {1024}, {
    type = "complex_double",
    origin = -math.pi,
    spacing = 2 * math.pi / 1024,
    initializer = function(i, x)
        return { math.cos(3 * x), math.sin(3 * x) }
    end
})

sim.log("wave rank=%d first=%0.2f+%0.2fi", wave:rank(), wave:values()[1][1], wave:values()[1][2])

2D Real Field for Diffusion Experiments

local ctx = sim.sim_create()
local grid = sim.sim_add_field(ctx, {256, 256}, { fill = 0.0 })

-- Drop a Gaussian bump into the center (Lua-side)
local vals = grid:values()
local function idx(x, y) return (y - 1) * 256 + x end
for y = 1, 256 do
  for x = 1, 256 do
    local dx = (x - 128) / 32
    local dy = (y - 128) / 32
    vals[idx(x, y)] = math.exp(-(dx * dx + dy * dy))
  end
end

Reading Parameters Mid-Run

Add fields and operators (sim_add_field, sim_add_stimulus_operator, etc.), step the context, then inspect fields:

local field = sim.sim_get_field(ctx, 0)
local info = sim.sim_field_info(ctx, 0)
sim.log("format=%s bytes=%d", info.format, info.byte_size)
local snapshot = field:values()

After grabbing snapshots, feed them into Lua visualizations or write them to disk; the Field handle remains valid as long as the context is alive.