---
title: "viewAHPtree: View an AHP tree"
#output: pdf_document
output: rmarkdown::html_vignette
vignette: >
  %\VignetteIndexEntry{viewAHPtree}
  %\VignetteEngine{knitr::rmarkdown}
  %\VignetteEncoding{UTF-8}
---

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

```{r setup}
library(AHPtools)
library(readxl)
```

# Introduction

This vignette shows how to use the viewAHPtree() function to build a hierarchical AHP structure from an Excel file. The example file is bundled with the package.

## Step 1: Load the example AHP file

```{r}
file <- system.file("extdata", "example_transport.xlsx", package = "AHPtools")
```

## Step 2: Read the AHP structure

We assume the AHP structure is in the "ahp" sheet.

```{r}
AHPstruc <- read_excel(file, sheet = "ahp")
print(AHPstruc, n=Inf)
```

## Step 3: Create the AHP Tree

```{r}
tree <- viewAHPtree(AHPstruc)
```

## Print the tree structure

```{r}
print(tree, "level", limit = NULL)
```

## Another example

```{r}
file <- system.file("extdata", "example_automobile.xlsx", package = "AHPtools")
AHPstruc2 <- read_excel(file, sheet = "AHP")
print(AHPstruc2, n=Inf)
tree <- viewAHPtree(AHPstruc2)
print(tree, "level", limit = NULL)
```

# Summary

The viewAHPtree() function processes the input data to build the hierarchical structure of criteria and sub-criteria used in AHP. This vignette demonstrates loading the data and visualizing the tree structure.