_sample_code.rmarkdown

---
title: "Sample Code"
format: html
editor: source
sidebar: false
---

```{r}
#| include: false
source("common_functions.R")
```






<!-- Check Your Understanding -->

::: {.callout-tip icon=false title="Check Your Understanding"}

TheInitialPromptGoesHere

-   Question1
-   Question2

:::



<!-- Folded code:  -->


```{r}
#| code-fold: true
#| code-summary: "Show the code"

code_goes_here <- 0
```




<!-- Tables -->

```{r}
#| label: tbl-LabelGoesHere
#| tbl-cap: "TitleGoesHere"

# make figure
```


<!-- Figures -->

```{r}
#| label: fig-LabelGoesHere
#| fig-cap: "TitleGoesHere"

# make figure
```



::: panel-tabset
#### first_tab

Stuff

#### second_tab

Stuff

#### third_tab

Stuff
:::




::: {.callout-note}
Text goes here.
:::

::: {.callout-warning}
Text goes here.
:::

::: {.callout-important}
Text goes here.
:::

::: {.callout-tip}
Text goes here. Color used for Check your understanding.
:::

::: {.callout-caution}
Text goes here.
:::



::: {.callout-note icon=false title="TitleGoesHere"}
This is a callout for a note with a title
:::

::: {.callout-tip appearance="minimal"}
This creates a callout box with no title
:::

::: {.callout-note}
Here is a note.
:::






<!-- Solutions at the bottom of the page -->

<a href="javascript:showhide('Solutions')"
style="font-size:.8em;">Class Activity</a>

::: {#Solutions style="display:none;"}

Solutions to Class Activity


```{r}
#| echo: false
stuff <- "here"
```


:::




# Fill in missing data
 tidyr::fill()


 
 
 
 

<!-- Beginning of two columns -->
::: columns
::: {.column width="45%"}

Stuff in first column

:::

::: {.column width="10%"}
<!-- empty column to create gap -->
:::

::: {.column width="45%"}

Stuff in second column

:::
:::
<!-- End of two columns -->





# Three column format

::: columns
::: {.column width="30%"}

Stuff in first column

:::

::: {.column width="5%"}
<!-- empty column to create gap -->
:::

::: {.column width="30%"}

Stuff in second column

:::

::: {.column width="5%"}
<!-- empty column to create gap -->
:::

::: {.column width="30%"}

Stuff in third column

:::
:::







# Generating R code for user


```{r}
#| echo: false
x <- c(1:5)
y <- x^2
df <- data.frame(x = x, y = y)
cat("x <- c(", paste(df$x, collapse = ", "),")\n")
cat("y <- c(", paste(df$y, collapse = ", "),")")
```

```{r}
#| echo: false

df <- data.frame(x = c(1:16)) |> mutate(y = x^2)
# build a string that gives the data
xy_string <- rep("",6)
xy_string[1] <- "sample_df <- data.frame("
xy_string[2] <- paste0(" \t x = c(", paste(df$x |> head(8), collapse = ", "), ", ")
xy_string[3] <- paste0(" \t  \t   ", paste(df$x |> tail(8), collapse = ", "), ")," )
xy_string[4] <- paste0(" \t y = c(", paste(df$y |> head(8), collapse = ", "), ", ")
xy_string[5] <- paste0(" \t  \t   ", paste(df$y |> tail(8), collapse = ", "), ")" )
xy_string[6] <- ")"
xystr <- paste(xy_string, " \n ", collapse="")

#| echo: false
cat(xystr)
```




## Plots


```{r}
#| eval: false

ts |> 
    autoplot(.vars = random) +
    geom_line(data = ts, aes(x = index, y = a_t), linewidth = 1) +
    labs(
      x = "Time",
      y = "Random",
      title = paste0("Random Component and EWMA (α = ", alpha, ")")
    ) +
    theme_minimal() +
    theme(
      plot.title = element_text(hjust = 0.5)
    )
```

```{r}
#| eval: false

ts |> 
    autoplot(.vars = random) +
    geom_line(data = ts, aes(x = index, y = a_t), color = "#D55E00", linewidth = 1) +
    labs(
      x = "Time",
      y = "Random",
      title = paste0("Random Component and EWMA (α = ", alpha, ")"),
      subtitle = "(All Dates)"
    ) +
    theme_minimal() +
    theme(
      plot.title = element_text(hjust = 0.5),
      plot.subtitle = element_text(hjust = 0.5)
    )
```


<!-- Formatting dates -->

```{r}
# Formatting dates
usd1_ts <- rio::import("data/exchange_rates.parquet") |>
  filter(currency == "USD.CAD") |>
  mutate(diff = rate - lag(rate)) |>
  as_tsibble(index = date) |>
  na.omit()

usd1_ts %>% 
  autoplot(.vars = rate) + 
    labs(
      title = "Converstion Rate for 1 USD to Canadian Dollars",
      subtitle = 
        paste0(
          format(min(usd1_ts$date), "%d %b %Y"),
            " - ",
          format(max(usd1_ts$date), "%d %b %Y")
          ),
      x = "Date",
      y = "Conversion Rate",
    ) +
    theme(
      plot.title = element_text(hjust = 0.5),
      plot.subtitle = element_text(hjust = 0.5)
    )
```

```{r}
#| echo: false
#| results: asis

# LaTeX math mode from a string

set.seed(6)
n <- 8
d_operator <- data.frame(t = c(1:n), x = sample(1:15, n, replace = FALSE)) |>
  mutate(diff = t - n)
cat( paste( paste0("$x_{t", ifelse(d_operator$t==n,"",d_operator$t-n), "} = ", d_operator$x, "$"), collapse = ",$~$ " ) ) 
cat( paste("$ x_t =", n, "$") )
# DO I need the cat()?
```

```{r}
# Create a time series based on the current year
# See 3-3 and 4-5
n_months <- 36
start_date <- my(paste(1, floor(year(now())-n_months/12)))
date_seq <- seq(start_date,
    start_date + months(n_months - 1),
    by = "1 months")
```


### Operators
Backward Shift Operator: $\mathbf{B}$
Difference operator: $\nabla$

### Ellipses
⋮

### Hyperlinks to pages

<!-- Bookmark -->
<a id="IDvalue">THING TO LINK TO</a>

<!-- Reference -->
<a href="https://byuistats.github.io/timeseries/chapter_4_lesson_2.html#DifferenceOperator">Chapter 4 Lesson 2</a>


<!-- Linear Imputation of Missing Values using the zoo package -->
<!-- See Lesson 5-2 -->