# start_finder function

# start_finder

## Overview

Finds R-based (1-indexed) positions where 1s begin episodes in a 0/1 vector (1 after 0 or at start). Useful for identifying episode starts.

## Inputs

- df: Dataframe whose first column is an integer vector of 0/1

## Returns

- start_index: Tibble of episode start positions (R index)

## Run documented examples

    example(start_finder, package = "cgmguru", run.dontrun = FALSE)
    #>
    #> strt_f> # Load sample data
    #> strt_f> library(iglu)
    #>
    #> strt_f> data(example_data_5_subject)
    #>
    #> strt_f> data(example_data_hall)
    #>
    #> strt_f> # Create a binary vector indicating episode starts
    #> strt_f> binary_vector <- c(0, 0, 1, 1, 0, 1, 0, 0, 1, 1)
    #>
    #> strt_f> df <- data.frame(episode_starts = binary_vector)
    #>
    #> strt_f> # Find R-based index where episodes start
    #> strt_f> start_points <- start_finder(df)
    #>
    #> strt_f> print(paste("Start index:", paste(start_points$start_index, collapse = ", ")))
    #> [1] "Start index: 3, 6, 9"
    #>
    #> strt_f> # Use with actual GRID results
    #> strt_f> grid_result <- grid(example_data_5_subject, gap = 15, threshold = 130)
    #>
    #> strt_f> grid_starts <- start_finder(grid_result$grid_vector)
    #>
    #> strt_f> print(paste("GRID episode starts:", length(grid_starts$start_index)))
    #> [1] "GRID episode starts: 99"
    #>
    #> strt_f> # Analysis on larger dataset
    #> strt_f> large_grid <- grid(example_data_hall, gap = 15, threshold = 130)
    #>
    #> strt_f> large_starts <- start_finder(large_grid$grid_vector)
    #>
    #> strt_f> print(paste("GRID episode starts in larger dataset:", length(large_starts$start_index)))
    #> [1] "GRID episode starts in larger dataset: 79"