---
title: "DSTG - Klasteriranje po ishodima"
output: 
  flexdashboard::flex_dashboard:
    social: menu
    orientation: columns
    vertical_layout: fill
    source_code: embed
---

```{css, echo=FALSE}
.sidebar { overflow: auto; }
.dataTables_scrollBody {
    height:95% !important;
    max-height:95% !important;
}
.chart-stage-flex {
    overflow:auto !important;
}
```

```{r setup, include=FALSE}
library(readxl)
library(tidyverse)
library(cluster)
library(knitr)
library(kableExtra)
library(tidyverse)
library(corrplot)
library(dendextend)
library(factoextra)

data1 <- read_excel('DSTG_ishodi.xlsx', sheet=1)
data1 <- na.omit(data1)

data2 <- data1 %>% select(LO_1:LO_6) 
data3 <- data.frame(scale(data2))

dist_student <- dist(data3)
hc_ward <- hclust(dist_student, method = "ward.D2")
ward_dend <- as.dendrogram(hc_ward) #%>% set("labels", 1:99)

ward_dend_color3 <- color_branches(ward_dend, k=3)
ward_dend_color4 <- color_branches(ward_dend, k=4)

klasteri3 <- cutree(hc_ward, k=3)
klasteri4 <- cutree(hc_ward, k=4)

data3_cluster3 <- data3 %>% mutate(klaster = klasteri3)
data3_cluster4 <- data3 %>% mutate(klaster = klasteri4)

data1_cluster3 <- data1 %>% mutate(klaster = klasteri3)
data1_cluster4 <- data1 %>% mutate(klaster = klasteri4)

AS <- data1 %>% summarise_at(vars(LO_1:LO_6), mean, na.rm = TRUE)

rez3 <- data1_cluster3 %>% group_by(klaster) %>% 
        summarise_at(vars(LO_1:LO_6), mean, na.rm = TRUE) %>% 
        gather(Ishod, Prosjek, LO_1:LO_6)
rez3 <- rez3 %>% 
        add_row(klaster=rep(0,6), Ishod=c("LO_1","LO_2","LO_3","LO_4","LO_5","LO_6"), 
                Prosjek=as.numeric(AS))
rez3$klaster <- factor(rez3$klaster)
levels(rez3$klaster) <- c("svi", "1", "2", "3")

rez4 <- data1_cluster4 %>% group_by(klaster) %>% 
        summarise_at(vars(LO_1:LO_6), mean, na.rm = TRUE) %>% 
        gather(Ishod, Prosjek, LO_1:LO_6)
rez4 <- rez4 %>% 
        add_row(klaster=rep(0,6), Ishod=c("LO_1","LO_2","LO_3","LO_4","LO_5","LO_6"), 
                Prosjek=as.numeric(AS))
rez4$klaster <- factor(rez4$klaster)
levels(rez4$klaster) <- c("svi", "1", "2", "3", "4")

bodovi <- c(10,14,26,8,26,16)

sil3 <- silhouette(data3_cluster3$klaster, dist(data3))
sil4 <- silhouette(data3_cluster4$klaster, dist(data3))

viz3 <- data3_cluster3 %>% gather(Ishod, Bodovi, LO_1:LO_6)
viz4 <- data3_cluster4 %>% gather(Ishod, Bodovi, LO_1:LO_6)

tablica <- data1 %>% rowwise() %>% mutate(ukupno = sum(c_across(LO_1:LO_6), na.rm = T)) %>% ungroup()
tablica3 <- tablica %>% mutate(klaster=klasteri3) %>% 
            group_by(klaster) %>% 
            arrange(desc(ukupno), .by_group = TRUE)
tablica4 <- tablica %>% mutate(klaster=klasteri4) %>% 
            group_by(klaster) %>% 
            arrange(desc(ukupno), .by_group = TRUE)

hl <- data.frame(Ishod=c("LO_1","LO_2","LO_3","LO_4","LO_5","LO_6"), 
                 Bodovi=c(10,14,26,8,26,16),
                 xcor1=rep(2.5,6), xcor2=rep(3,6), ycor=c(12,16,28,10,28,18))
```


Dendrogram {data-navmenu="Tri klastera"}
=======================================================================

Column {data-width=800}
-------------------------------------

### Tri klastera
```{r fig.width=18,fig.height=10}
plot(ward_dend_color3)
```

Column {data-width=100}
-------------------------------------

### Broj studenata u klasterima
```{r}
data3_cluster3 %>% count(klaster)
```

Silhouette {data-navmenu="Tri klastera"}
=======================================================================

Column {data-width=600}
-------------------------------------

### Silhouette
```{r}
fviz_silhouette(sil3, print.summary=FALSE)
```

Column {data-width=300}
-------------------------------------

### info
```{r}
summary(sil3)
```

Vizualizacija klastera {data-navmenu="Tri klastera"}
=======================================================================

Column {data-width=250}
-------------------------------------

### Funkcije gustoća za pojedini ishod

```{r}
ggplot(viz3, aes(x=Bodovi, fill=Ishod, color=Ishod)) + 
  geom_density(alpha=.2) +
  facet_wrap(~Ishod) + theme(legend.position="none") + ylim(0,1.5)
```

Column {data-width=500}
-------------------------------------

### Funkcije gustoća za pojedini ishod unutar klastera

```{r}
ggplot(viz3, aes(x=Bodovi, fill=Ishod, color=Ishod)) + 
  geom_density(alpha=.2) + facet_grid(klaster ~ Ishod) + ylim(0,1.5) +
  theme(axis.text.x = element_text(angle = 90, vjust = 0.5, hjust=1),legend.position="none")
```

Dendrogram {data-navmenu="Četiri klastera"}
=======================================================================

Column {data-width=800}
-------------------------------------

### Četiri klastera
```{r fig.width=18,fig.height=10}
plot(ward_dend_color4)
```

Column {data-width=100}
-------------------------------------

### Broj studenata u klasterima
```{r}
data3_cluster4 %>% count(klaster)
```

Silhouette {data-navmenu="Četiri klastera"}
=======================================================================

Column {data-width=600}
-------------------------------------

### Silhouette
```{r}
fviz_silhouette(sil4, print.summary=FALSE)
```

Column {data-width=300}
-------------------------------------

### info
```{r}
summary(sil4)
```

Vizualizacija klastera {data-navmenu="Četiri klastera"}
=======================================================================

Column {data-width=250}
-------------------------------------

### Funkcije gustoća za pojedini ishod

```{r}
ggplot(viz4, aes(x=Bodovi, fill=Ishod, color=Ishod)) + 
  geom_density(alpha=.2) +
  facet_wrap(~Ishod) + theme(legend.position="none") + ylim(0,1.5)
```

Column {data-width=500}
-------------------------------------

### Funkcije gustoća za pojedini ishod unutar klastera

```{r}
ggplot(viz4, aes(x=Bodovi, fill=Ishod, color=Ishod)) + 
  geom_density(alpha=.2) + facet_grid(klaster ~ Ishod) + ylim(0,1.5) +
  theme(axis.text.x = element_text(angle = 90, vjust = 0.5, hjust=1),legend.position="none")
```

Funkcije gustoća {data-navmenu="Usporedbe klastera"}
=======================================================================

Column {data-width=500}
-------------------------------------

### Tri klastera

```{r fig.height=4}
ggplot(viz3, aes(x=Bodovi, fill=Ishod, color=Ishod)) + 
  geom_density(alpha=.2) + facet_grid(klaster ~ Ishod) + ylim(0,1.5) +
  theme(axis.text.x = element_text(angle = 90, vjust = 0.5, hjust=1),legend.position="none")
```

Column {data-width=500}
-------------------------------------

### Četiri klastera

```{r}
ggplot(viz4, aes(x=Bodovi, fill=Ishod, color=Ishod)) + 
  geom_density(alpha=.2) + facet_grid(klaster ~ Ishod) + ylim(0,1.5) +
  theme(axis.text.x = element_text(angle = 90, vjust = 0.5, hjust=1),legend.position="none")
```

Tablice studenata {data-navmenu="Usporedbe klastera"}
=======================================================================

Column {data-width=500}
-------------------------------------

### Tri klastera

```{r}
tablica3 %>%
  kbl(caption = "Tablica s tri klastera") %>%
  kable_classic("hover",full_width = F, html_font = "Cambria")
```

Column {data-width=500}
-------------------------------------

### Četiri klastera

```{r}
tablica4 %>%
  kbl(caption = "Tablica s četiri klastera") %>%
  kable_classic("hover",full_width = F, html_font = "Cambria")
```

Planirani i ostvareni bodovi (slika1) {data-navmenu="Usporedbe klastera"}
=======================================================================

Column {.tabset .tabset-fade}
-----------------------------------------------------------------------

### Tri klastera

```{r fig.width=15}
ggplot(rez3, aes(x=Ishod, y=Prosjek, fill=klaster, color=klaster)) + 
  geom_bar(stat="identity", width=0.4, position = position_dodge(width=0.9)) +
  geom_segment(aes(x=0.6,xend=1.4,y=bodovi[1],yend=bodovi[1]),color="black") +
  geom_segment(aes(x=1.6,xend=2.4,y=bodovi[2],yend=bodovi[2]),color="black") +
  geom_segment(aes(x=2.6,xend=3.4,y=bodovi[3],yend=bodovi[3]),color="black") +
  geom_segment(aes(x=3.6,xend=4.4,y=bodovi[4],yend=bodovi[4]),color="black") +
  geom_segment(aes(x=4.6,xend=5.4,y=bodovi[5],yend=bodovi[5]),color="black") +
  geom_segment(aes(x=5.6,xend=6.4,y=bodovi[6],yend=bodovi[6]),color="black") +
  geom_text(x=1, y=10.7, label=bodovi[1], color="black") +
  geom_text(x=2, y=14.7, label=bodovi[2], color="black") +
  geom_text(x=3, y=26.7, label=bodovi[3], color="black") +
  geom_text(x=4, y=8.7, label=bodovi[4], color="black") +
  geom_text(x=5, y=26.7, label=bodovi[5], color="black") +
  geom_text(x=6, y=16.7, label=bodovi[6], color="black") +
  geom_text(aes(label=round(Prosjek,2)), position=position_dodge(width=0.9), vjust=-0.5)
```

### Četiri klastera

```{r fig.width=15}
ggplot(rez4, aes(x=Ishod, y=Prosjek, fill=klaster, color=klaster)) + 
  geom_bar(stat="identity", width=0.4, position = position_dodge(width=0.9)) +
  geom_segment(aes(x=0.6,xend=1.4,y=bodovi[1],yend=bodovi[1]),color="black") +
  geom_segment(aes(x=1.6,xend=2.4,y=bodovi[2],yend=bodovi[2]),color="black") +
  geom_segment(aes(x=2.6,xend=3.4,y=bodovi[3],yend=bodovi[3]),color="black") +
  geom_segment(aes(x=3.6,xend=4.4,y=bodovi[4],yend=bodovi[4]),color="black") +
  geom_segment(aes(x=4.6,xend=5.4,y=bodovi[5],yend=bodovi[5]),color="black") +
  geom_segment(aes(x=5.6,xend=6.4,y=bodovi[6],yend=bodovi[6]),color="black") +
  geom_text(x=1, y=10.7, label=bodovi[1], color="black") +
  geom_text(x=2, y=14.7, label=bodovi[2], color="black") +
  geom_text(x=3, y=26.7, label=bodovi[3], color="black") +
  geom_text(x=4, y=8.7, label=bodovi[4], color="black") +
  geom_text(x=5, y=26.7, label=bodovi[5], color="black") +
  geom_text(x=6, y=16.7, label=bodovi[6], color="black") +
  geom_text(aes(label=round(Prosjek,2)), position=position_dodge(width=0.9), vjust=-0.5)
```

Planirani i ostvareni bodovi (slika2) {data-navmenu="Usporedbe klastera"}
=======================================================================

Column {.tabset .tabset-fade}
-----------------------------------------------------------------------

### Tri klastera

```{r fig.width=10}
ggplot() + 
  geom_bar(data=rez3, aes(x=klaster, y=Prosjek, fill=klaster, color=klaster), stat="identity", width=0.65, position = position_dodge(width=0.9)) +
  facet_wrap(~Ishod) + 
  geom_hline(data= hl, aes(yintercept=Bodovi)) +
  geom_text(data = hl, aes(x=xcor1, y=ycor, label=Bodovi)) +
  geom_text(data=rez3, aes(x=klaster, y=Prosjek, label=round(Prosjek,2)), vjust=1.5)
```


### Četiri klastera

```{r fig.width=10}
ggplot() + 
  geom_bar(data=rez4, aes(x=klaster, y=Prosjek, fill=klaster, color=klaster), stat="identity", width=0.75, position = position_dodge(width=0.9)) +
  facet_wrap(~Ishod) + 
  geom_hline(data= hl, aes(yintercept=Bodovi)) +
  geom_text(data = hl, aes(x=xcor2, y=ycor, label=Bodovi)) +
  geom_text(data=rez4, aes(x=klaster, y=Prosjek, label=round(Prosjek,2)), vjust=1)
```

Planirani i ostvareni bodovi (slika3) {data-navmenu="Usporedbe klastera"}
=======================================================================

Column {data-width=500}
-------------------------------------

### Tri klastera

```{r fig.width=9}
ggplot(data=rez3, aes(x=klaster, y=Prosjek, fill=klaster, color=klaster)) + 
  geom_bar(stat="identity", width=0.65, position = position_dodge(width=0.9)) +
  geom_text(aes(label=round(Prosjek,2)), vjust=-0.3) + expand_limits(y = c(0, 27)) +
  facet_wrap(~Ishod, scales="free",
             labeller=as_labeller(c(LO_1="LO_1 (max: 10)", LO_2="LO_2 (max: 14)", LO_3="LO_3 (max: 26)",
                                  LO_4="LO_4 (max: 8)", LO_5="LO_5 (max: 26)", LO_6="LO_6 (max: 16)")))
```

Column {data-width=500}
-------------------------------------

### Četiri klastera

```{r fig.width=9}
ggplot(data=rez4, aes(x=klaster, y=Prosjek, fill=klaster, color=klaster)) + 
  geom_bar(stat="identity", width=0.65, position = position_dodge(width=0.9)) +
  geom_text(aes(label=round(Prosjek,2)), vjust=-0.3) + expand_limits(y = c(0, 27)) +
  facet_wrap(~Ishod, scales="free",
             labeller=as_labeller(c(LO_1="LO_1 (max: 10)", LO_2="LO_2 (max: 14)", LO_3="LO_3 (max: 26)",
                                    LO_4="LO_4 (max: 8)", LO_5="LO_5 (max: 26)", LO_6="LO_6 (max: 16)")))
```