map2_example_nls.multstart.R

# example of map2

# load packages
library(nls.multstart)
library(rTPC)
library(tidyverse)

# load data and keep only 2 curves
data("chlorella_tpc")
d <- chlorella_tpc %>%
  filter(curve_id <=2)

# nest data frame
d <- group_by(d, curve_id, process, flux, growth_temp) %>%
  nest()

# calculate start values for each curve and add them as a list element
d <- mutate(d, start_vals = map(data, ~get_start_vals(.x$temp, .x$rate, model_name = 'gaussian_1987')))

# look at d
d

d$start_vals[[1]]

# fit nls.multstart to each unique dataset with each unique set of start values using map2
d <- mutate(d, fit = map2(data, start_vals, ~nls_multstart(rate~gaussian_1987(temp = temp, rmax,topt,a),
                                                                     data = .x,
                                                                     iter = c(3,3,3),
                                                                     start_lower = .y - 10,
                                                                     start_upper = .y + 10,
                                                                     supp_errors = 'Y',
                                                                     convergence_count = FALSE)))

d$fit[[1]]
d$fit[[2]]