Ülesanne 4.Rmd

---
title: "ÜLESANNE 4. Graafiteooria"

subtitle: "NTR0390 Algoritmid ja andmestruktuurid. Moodul GRAAFID"

author: "<br>õpilane Toomas Kirsing <br>"

date: "04.11.2022 <br>"


output: 
  html_document:
    toc: true
    toc_depth: 3
    toc_float: 
      collapsed: true
    number_sections: false
    theme: default
---

```{r, message=FALSE, warning=FALSE}
if (!"BiocManager" %in% rownames(installed.packages()))
    install.packages("BiocManager", repos = "https://cran.r-project.org")
    .bioc_packages <- c("RBGL")
    BiocManager::install(.bioc_packages)
library(RBGL)
library(igraph)
library(sf)
library(ggplot2)
library(stringr)
```

# Ülesanne

### Graafi moodustamine 

Üliõpilaskoodist (212452) a=2

```{r, message=FALSE, warning=FALSE}
a = 2
RNGkind(sample.kind = "Rounding") 
set.seed(212452)
g<-erdos.renyi.game(round(a/2)+8, 0.6)
plot(g,layout=layout_in_circle)
```

### Planaarsuse kontroll

```{r message=FALSE, warning=FALSE}
boyerMyrvoldPlanarityTest(as_graphnel(g))
```
Graaf ei ole planaarne

```{r message=FALSE, warning=FALSE}
#G <- contract(g, c(1,2,3,4,5,6,7,8,9,10), vertex.attr.comb=toString)
#plot(simplify(G),layout=layout_in_circle)
```
Viskab errori:
```{r message=FALSE, warning=FALSE}
#Quitting from lines 52-54 (Ülesanne-4.Rmd) 
#Error in contract(g, c(1, 2, 3, 4, 5, 6, 7, 8, 9, 10), vertex.attr.comb = toString) : 
#  At core/operators/contract.c:77 : Invalid mapping vector length, Invalid value
#Calls: <Anonymous> ... eval_with_user_handlers -> eval -> eval -> contract
#In addition: Warning messages:
#1: package(s) not installed when version(s) same as or greater than current; use
#  `force = TRUE` to re-install: 'RBGL' 
```

### Graafi tippude värvimine

```{r message=FALSE, warning=FALSE}
V(g)$name <- c(1:10)
col <- rep("white",length(V(g)))
col[largest_ivs(g)[[1]]] <- 2
i = 3
g1 <- g
while(length(g1) > 0){
  g2 <- g1
  g2 <- delete.vertices(g1, V(g1)[(V(g1)%in%largest_ivs(g1)[[1]])])
  col[V(g)$name%in%largest_ivs(g1)[[1]]$name] <- i
  g1 <- g2
  i = i+1
}
plot(g,vertex.color=col,layout=layout_in_circle)
```

### Kromaatiline arv

```{r message=FALSE, warning=FALSE}
max(greedy_vertex_coloring(g))
```

# Boonusülesanne
```{r message=FALSE, warning=FALSE}
download.file("https://geoportaal.maaamet.ee/docs/haldus_asustus/maakond_shp.zip",destfile="maakond_shp.zip")
unzip("maakond_shp.zip")
county <- st_read(list.files(pattern = ".shp")[1])
county_smpl <- st_simplify(county, preserveTopology = T, dTolerance = 200)
ggplot()+geom_sf(data = county_smpl)
county$MNIMI <- str_replace(county$MNIMI, " maakond", "")
ggplot(data = county_smpl)+
geom_sf(aes(fill = MNIMI))+
geom_sf_text(aes(label = MNIMI), colour="grey50")+
guides(fill= "none")+
theme(axis.title.x=element_blank(),axis.title.y=element_blank())
```

# Kasutatud allikad

* Moodle materjalid