options(width = 300)
library(ggplot2)
library(tidyr)

# Create the RT column with values ranging from -20 to 40
RT <- seq(4, 10, by = 1)

# Create the column names for Kz
z_values <- seq(30, 50, by = 5)
col_names <- paste0("K", z_values)

# Create an empty dataframe with the desired columns
df <- data.frame(RT = RT)

# Loop through the z_values and calculate the Kz values using the formula
for (z in z_values) {
  Kz <- (((273.15 + z) / ((273.15 + z) - (273.15 + df$RT))))*0.4
  col_name <- paste0("K", z)
  df[col_name] <- Kz
}

# Print the resulting dataframe
library(dplyr)

# Replace negative values and infinite values with N/A
df[, -1] <- df[, -1] %>%
  mutate_all(~ ifelse(. < 0 | !is.finite(.), NA, .))
df
# Reshape the data into a longer format
df_long <- df %>%
  gather(key = "K", value = "Value", -RT)

# Convert K column values to numeric
df_long$K <- as.numeric(gsub("K", "", df_long$K))

# Plot the line chart
plot <- ggplot(df_long, aes(x = RT, y = Value, color = factor(K))) +
  geom_line() +
  labs(x = "RT", y = "Value", color = "K") +
  ylim(0, 6)+  # Set the y-axis limit to 15
  scale_color_discrete(name = "K")

# Save the plot as a PDF file
ggsave("line_chart.pdf", plot, width = 8, height = 6)