quanti {PROSPER}

Step by step: the model develops driven by field data

Description

This is a working horse of PROSPER. It quantifies the number or the proportion of individuals entering the next development stage using predefined formulas (formul). Typically these formulas are the results of experiments.

Usage

quanti(
  origin = NA,
  step_name,
  crop,
  proportion = TRUE,
  equal_dis = TRUE,
  res_max = NA,
  res_min = 0,
  formul = NA,
  area,
  addit_variables = NA,
  log_values = TRUE,
  back_log = TRUE
)

Arguments

origin

numbers or log-numbers of individuals at the start for every genotype. numeric. Alternatively the columnaes of dfgenotype can be used.

step_name

step name in the database containing the model parameters. character.

crop

current crop in the crop sequence, must fit to one of the crop names in the data frame with weed-parameters. character.

proportion

logical, TRUE when the output should be a proportion, otherwise it will be an absolute number.

equal_dis

logical, TRUE when the distribution of the weeds is spatially uniform across the area.

res_max

output maximum, ignored when origin=NA. numeric.

res_min

output minimum. numeric.

formul

character. See details.

area

number of area units. positive numeric.

addit_variables

variables used in formul that are not predefined in param.weed. See details. character vector

log_values

logical, TRUE when origin in log-scale.

back_log

logical, TRUE when the output is in log-scale. Only used when proportion==FALSE.

Details

Within PROSPER simulation models are build up with discrete simulation steps. These steps are conducted by functions like pop_step or gen_reprod. These functions affect the complete population and need a count of individuals or a proportion of the population that are affected of the specific simulation step. These numbers are calculated with quanti. The calculation is based on the data provided in weed-parameters. There a model is given for every parameter in the table. The parameter formul allows to use a different model if necessary. If no model is given at all, the simulation step is assumed to consist only of one value. The parameters of param.weed are normal distributed and the SE is used to draw them for the current calculation using rnorm(). These values are used to evaluate the model for simulation step. The resulting count or proportion can be used to perform the simulation step for the population.

Value

Either a (log-)number of individuals or a proportion resp. a rate.

See Also

pop_step pop_germc weed-parameters

Examples

#loads the example data for Echinochloa crus-galli
data(param.ECHCG)
param.weed <- param.ECHCG
#how many seeds (natural, not log-scale) prodused by 100 plants in a corn stand on 100 area units?
quanti(origin=100, step_name="seed_prod_first", crop="corn",  proportion=FALSE,
                 area=100, log_values=FALSE, back_log=FALSE)
rm(param.ECHCG)