---
title: "Assignment 2"
subtitle: "BIOL6994/BIOL6997"
author: "Sebastian A. Cruz Romero"
date: "`r format(Sys.time(), '%Y-%b-%d, %I: %M %p')`"
output:
  prettydoc::html_pretty:
    theme: cayman
    highlight: github
---

## Q1. Using functions

```{r q1}
BOD_list <- as.list(BOD)
head(BOD_list, 6)
```

## Q2. Converting matrix into DataFrame

```{r q2}
df1 <- data.frame(
  Name = c("a", "b", "c", "d"),
  Age = c(12, 34, 23, 67),
  BMI = c(22, 12, 10, 11),
  Country = c("Malaysia", "India", "Spain", "England")
)
head(df1, 6)
```

## Q3. Accessing 1st & 2nd rows

```{r q3}
df <- data.frame(
  Name = c(
    "Raju", "Kumar", "Chandru", "Deepak", "Raina",
    "Dhoni", "Hema", "Vandana", "Bela", "Anand"
  ),
  Age = c(12, 34, 23, 67, 23, 43, 23, 38, 34, 12),
  Gender = c("M", "M", "M", "M", "M", "M", "F", "F", "F", "M"),
  Country = c(
    "Malaysia", "India", "Spain", "England", "Malaysia",
    "Malaysia", "India", "Egypt", "Italy", "Peru"
  )
)

first_two_rows <- df[1:2, ]
head(first_two_rows, 6)
```

## Q4. Accessing 1st & 2nd columns

```{r q4}
first_two_columns <- df[, 1:2]
head(first_two_columns, 6)
```

## Q5. Sorting the dataframe

```{r q5}
sorted_df <- df[order(df$Age), ]
head(sorted_df, 6)
```

## Q6. Adding a new column

```{r q6}
df_with_score <- df
df_with_score$Score <- c(85, 90, 78, 88, 90, 92, 80, 90, 87, 100)
head(df_with_score, 6)
```

## Q7. Filtering rows with a condition

```{r q7}
age_over_30 <- df[df$Age > 30, ]
head(age_over_30, 6)
```

## Q8. Renaming columns

```{r q8}
renamed_df <- df
names(renamed_df) <- c("Person", "Years", "Gender", "Nation")
head(renamed_df, 6)
```

## Q9. Selecting multiple conditions

```{r q9}
selected_rows <- df1[df1$Age > 20 & df1$BMI < 15, ]
head(selected_rows, 6)
```

## Q10. Summarizing a column

```{r q10}
average_age <- mean(df1$Age)
head(average_age, 6)
```