# Initialization

The following inputs control how a calculation is initialized. They must be defined with the prefix `mfix`:

| Description | Type | Default
--- | --- | --- | ---
do_initial_proj | Perform an initial projection. | Bool | true
initial_iterations | Number of pressure iterations to execute before time-marching. | Int | 3
scale_init_dt | Factor by which `dt` is scaled in the initial iterations and step. Must be a value <= 1.0 | Real | 1.0
restart | If set, then restart from this file rather than from scratch. | String | None
repl_x | Replicate initial data by this factor in the x-direction. | Int | 1
repl_y | Replicate initial data by this factor in the y-direction. | Int | 1
repl_z | Replicate initial data by this factor in the z-direction. | Int | 1