R Bridge Week 1 Assignment

#1. Write a loop that calculates 12-factorial
FactorialLoop <- function(Num)
  {
    Result <- 1 # initialize Result variable as 1
    for (i in 1:Num) # Loop through 1 to input Num
    {
      Result <- Result * i # Multiply numbers in loop and store in Result
    }
    print(Result) # Print final Result
}

FactorialLoop(12) # Get 12!

## [1] 479001600

#2. Show how to create a numeric vector that contains the sequence from 20 to 50 by 5
SeqVector <- seq(20,50,5) # Create vector from 20 to 50 stepping by 5

SeqVector

## [1] 20 25 30 35 40 45 50

#3. Create the function “factorial” that takes a trio of input numbers a, b, and c and solve the quadratic equation. 
FactorialFunc <- function(a, b, c) 
{
  delta <- b^2 - (4*a*c) # Create delta variable used in square root 
  if (delta >= 0) # Look to see if results will be real
  {
    x1 <- (-b + sqrt(delta))/(2*a)
    x2 <- (-b - sqrt(delta))/(2*a)
  }
  else # Look to see if results will be imaginary
  {
    x1 <- as.complex((-b + sqrt(-delta))/(2*a)) #Multiply delta by -1 and make complex
    x2 <- as.complex((-b - sqrt(-delta))/(2*a))
  }
  print(paste("x1 =", x1))
  print(paste("x2 =", x2))

}

FactorialFunc(1,4,4)

## [1] "x1 = -2"
## [1] "x2 = -2"