Varying line thickness in R

Is it possible to have a varying line thickness between two points using ggplot in R ie If there are 2 points A & B, a line should be connecting those 2 points starting from A. Only condition is the thickness of the line should vary like at the start, line should be thin and at the end, line should be thick, there is no other points are present in between A & B ?

It is a bit difficult to understand what exactly you are interested in without seeing what you have already tried.

However, here is how you can plot a line with ggplot2 between two points, i.e., point_a and point_b, while the line increases in width.

# Define your points.
point_a <- 1
point_b <- 10

# Some dummy data.
x <- seq(point_a, point_b, length.out = 100)

# Create data frame.
data <- data.frame(x = x, y = x)

# Plot a line with varying width.
ggplot(data, aes(x = x, y = y)) +
    geom_line(linewidth = x)

The code above will produce the following plot:

Feel free to comment if this is not what you had in mind.

If you don't want to manually interpolate linewidths, you can use geom_link2 from the ggforce package:

library(ggforce)
#> Loading required package: ggplot2

df <- data.frame(x = c(1, 2, 4), y = c(3, 1, 7), width = c(1, 10, 5))

ggplot(df, aes(x, y,  linewidth = width)) +
  geom_link2(lineend = "round", color = "green3") +
  theme_minimal(base_size = 16)

^{Created on 2023-05-06 with reprex v2.0.2}