---
title: "Combining tables"
output: rmarkdown::html_vignette
vignette: >
  %\VignetteIndexEntry{Combining tables}
  %\VignetteEncoding{UTF-8}
  %\VignetteEngine{knitr::rmarkdown}
editor_options: 
  chunk_output_type: console
---

```{r, include = FALSE}
knitr::opts_chunk$set(
  collapse = TRUE,
  comment = "#>"
)
```

```{r, echo=TRUE, message=FALSE, warning=FALSE}
library(gapminder)
library(dplyr)
library(tidyr)
library(stringr)
library(purrr)
library(gt)
library(mmtable2)
# devtools::install()
```

## Combining tables

You can combine tables with `+`, `/` and `*` operators.
```{r,echo=FALSE, message=FALSE, warning=FALSE, paged.print=FALSE, out.width = "600px"}
create_table <- function(df,name){
 df %>%
   mmtable(cells = value,table_name = name) +
   header_top(year) +
   header_left(country) +
   header_top_left(var)  +
   header_left_top(continent)
}
```

```{r, echo=FALSE,message=FALSE, warning=FALSE, paged.print=FALSE, out.width = "600px"}
gapminder_tbl <-
 gapminder_mm %>%
 mutate(continent_n = continent, var_n = var) %>%
 group_by(continent_n,var_n) %>% nest() %>%
 ungroup() %>% 
 filter(
   (continent_n == "Oceania" & var_n == "Population") | 
   (continent_n == "Oceania" & var_n == "GDP") |
   (continent_n == "Asia" & var_n == "Population") |
   (continent_n == "Asia" & var_n == "GDP"))  %>% 
 arrange(continent_n,var_n) %>% 
 mutate(name = paste("Table",row_number(), sep =" " )) %>% 
 mutate(table =map2(data,name,create_table))
```

```{r,echo=FALSE, message=FALSE, warning=FALSE, paged.print=FALSE, out.width = "600px"}
t1 <- gapminder_tbl %>% filter(name == "Table 1") %>% pull(table) %>% .[[1]]
t2 <- gapminder_tbl %>% filter(name == "Table 2") %>% pull(table) %>% .[[1]]
t3 <- gapminder_tbl %>% filter(name == "Table 3") %>% pull(table) %>% .[[1]]
t4 <- gapminder_tbl %>% filter(name == "Table 4") %>% pull(table) %>% .[[1]]
```

The `+` operator places tables side-by-side (sharing headers)  
```{r message=FALSE, warning=FALSE, echo = T}
ex1 <- t1 + t2
print(ex1)
```

The `/` operator places tables on top of one another (sharing headers)  
```{r message=FALSE, warning=FALSE, echo = T}
ex2 <- t1 / t3
print(ex2)
```

The `*` operator "integrates" tables  
```{r message=FALSE, warning=FALSE, echo = T}
ex3 <- t1 * t3 * t4 *  t2
print(ex3)
```