---
title: "Lesson 7"
format: html
---


```{r}
require(tidyverse)


files <- c(
  "../../data/01-sales.csv",
  "../../data/02-sales.csv",
  "../../data/03-sales.csv"
)

files <- dir("../../data", pattern = "sales.csv", full.names = TRUE)


readr::read_csv(files, id = "file") |>
  mutate(file = basename(file))
```


```{r}
require(tidyverse)
library(tidyverse)

files <- dir(
  "../../data/gapminder",
  pattern = "^[12][09][0-9][0-9].xlsx$",
  full.names = TRUE
)


alldf <- tibble::tibble()
for (file in files) {
  alldf <- alldf |>
    bind_rows(
      readxl::read_xlsx(file) |>
        mutate(year = parse_number(basename(file)))
    )
}

alldf |>
  ggplot(aes(x = lifeExp, y = gdpPercap)) +
  geom_point(aes(color = factor(year))) +
  geom_smooth(method = "lm", se = FALSE) +
  scale_y_log10(
    breaks = scales::trans_breaks("log10", function(x) 10^x),
    labels = scales::trans_format("log10", scales::math_format(10^.x))
  ) +
  facet_wrap(~year, ncol = 4, scale = "fixed")
```

# slope

```{r}
file <- files[1]

lm(y ~ x, data)

m <- lm(log10(gdpPercap) ~ lifeExp, readxl::read_xlsx(file))

summary(m)

coef(m)[2]

slopes <- c()
years <- c()
for (file in files) {
  m <- lm(log10(gdpPercap) ~ lifeExp, readxl::read_xlsx(file))
  years <- c(years, parse_number(basename(file)))
  slopes <- c(slopes, coef(m)[2])
}
years
slopes


plot(years, as.numeric(slopes), type = "b")
```

# purrr



```{r}
require(tidyverse)
df <- tibble(
  filename = dir(
    "../../data/gapminder",
    pattern = "^[12][09][0-9][0-9].xlsx$",
    full.names = TRUE
  )
) |>
  dplyr::mutate(
    data = purrr::map(
      filename,
      \(x) readxl::read_xlsx(x)
    )
  ) |>
  mutate(year = parse_number(basename(filename))) |>
  mutate(
    m = purrr::map(data, \(xxxx) lm(log10(gdpPercap) ~ lifeExp, data = xxxx))
  ) |>
  mutate(slope = purrr::map_dbl(m, \(yyyy) coef(yyyy)[2])) |>
  unnest(data)

pvalue <- summary(df$m[[1]])$coefficients[2, 4]
rsq <- summary(df$m[[1]])$r.squared

require(tidymodels)
generics::tidy(df$m[[1]])

df |>
  ggplot(aes(x = lifeExp, y = gdpPercap)) +
  geom_point(aes(color = factor(year))) +
  geom_smooth(method = "lm", se = FALSE) +
  scale_y_log10(
    breaks = scales::trans_breaks("log10", function(x) 10^x),
    labels = scales::trans_format("log10", scales::math_format(10^.x))
  ) +
  facet_wrap(~year, ncol = 4, scale = "fixed")


df |>
  ggplot(aes(x = year, y = slope)) +
  geom_line() +
  geom_point()


df
df$slope[[1]]

coef(df$m[[1]])[2]

lm(y ~ x, data)


df |>
  unnest(data) |>
  ggplot(aes(x = lifeExp, y = gdpPercap)) +
  geom_point(aes(color = factor(year))) +
  geom_smooth(method = "lm", se = FALSE) +
  scale_y_log10(
    breaks = scales::trans_breaks("log10", function(x) 10^x),
    labels = scales::trans_format("log10", scales::math_format(10^.x))
  ) +
  facet_wrap(~year, ncol = 4, scale = "fixed")
```