## Tuesday, 4 December 2018

### R provides a number of commands for writing output

R provides a number of commands for writing output to a file
r <- 0.11 # Annual interest rate
> term <- 10 # Forecast duration (in years)
> period <- 1/12 # Time between payments (in years)
> payments <- 100
> r <- 0.11 # Annual interest rate
> n <- floor(term/period)
> pension <- 0
> (i in 1:n) {

for (i in 1:n) {
+   pension[i+1] <- pension[i]*(1 + r*period) + payments
+ }
> time <- (0:n)*period
> plot(time, pension)

> x <- seq(0, 5, by = 0.01)
> > y.upper <- 2*sqrt(x)
> y.lower <- -2*sqrt(x)
> y.max <- max(y.upper)
> y.upper <- 2*sqrt(x)
> y.max <- max(y.upper)
> plot(c(-2, 5), c(y.min, y.max), type = "n", xlab = "x", ylab = "y")
> plot(c(-2, 5), c(y.min, y.max), type = "n", xlab = "x", ylab = "y")
> y.min <- min(y.lower)
> plot(c(-2, 5), c(y.min, y.max), type = "n", xlab = "x", ylab = "y")
> lines(x, y.upper)
> lines(x, y.lower)
> abline(v=-1)

> points(1, 0)
> text(1, 0, "focus (1, 0)", pos=4)
> text(-1, y.min, "directrix x = -1", pos = 4)
> title("The parabola y^2 = 4*x")
> par(mfrow = c(2, 2), mar=c(5, 4, 2, 1))
> curve(x*sin(x), from = 0, to = 100, n = 1001)
> curve(x*sin(x), from = 0, to = 10, n = 1001)
> curve(x*sin(x), from = 0, to = 1, n = 1001)
> curve(x*sin(x), from = 0, to = 0.1, n = 1001)

> par(mfrow = c(1, 1))