linear_interpolation: Model piecewise linear decline in vaccine efficacy or other...
In MattWiener/heemodFits: Using Survival Fits with Heemod

Description Usage Arguments Details Value Examples

Model piecewise linear decline in vaccine efficacy or other variables

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linear_interpolation(marked_cycles, marked_values, init_value = 1,
  change_per_cycle, max_change_cycles, age_start_change_per_cycle = NULL,
  cycle_length = 1, cycles = NULL, age_at_cycle_0, min_val = -Inf)

`marked_cycles`	cycles at which effectiveness fractions are specified.
`marked_values`	effectiveness fractions at the corresponding cycles.
`init_value`	a point at (0, init_value) will be added
`change_per_cycle`	can be specified instead of `marked_cycles` and `marked_times`. If both are specified, `marked_cycles` and `marked_values` take precedence.
`max_change_cycles`	used with change_per_cycle
`age_start_change_per_cycle`	at what age should the decline in efficacy start (if not specified, there's no threshold).
`cycle_length`	used to calculate age from cycles if necessary
`cycles`	The cycles for which values should be returned. If `NULL`, the default, a function is returned.
`age_at_cycle_0`	used in conjunction with `age_start_change_per_cycle`.
`min_val`	minimum value the interpolation can take on.

intended for use in parameters object for heemod models.

a function that calculates the decline in efficacy based on cycle and, if specified, patient age at the start of a simulation.

linear_interpolation(c(1, 10, 20), c(1, .5, .25))
linear_interpolation(change_per_cycle = -0.02, max_change_cycles = 50)
linear_interpolation(change_per_cycle = -0.02, max_change_cycles = 100,
   min_val = -0.4)
linear_interpolation(age_start_change_per_cycle = 65, age_at_cycle_0 = 60,
  change_per_cycle = -0.05, cycles = 1:15, max_change_cycles = 5)