Vectorized operations

You can extend the concept of relational operators to vectors of any arbitrary length. Compare two vectors using > to get a logical vector back of the same length, holding TRUE when the first is greater than the second, and FALSE otherwise.

apple <- c(120.00, 120.08, 119.97, 121.88)
datacamp  <- c(118.5, 124.21, 125.20, 120.22)

apple > datacamp
[1]  TRUE FALSE FALSE  TRUE

Comparing a vector and a single number works as well. R will recycle the number to be the same length as the vector:

apple > 120
[1] FALSE  TRUE FALSE  TRUE

Imagine how this could be used as a buy/sell signal in stock analysis! A data frame, stocks, is available for you to use.

Este exercício faz parte do curso

Intermediate R for Finance

Instruções do exercício

Print stocks.
You want to buy ibm when it crosses below 175. Use $ to select the ibm column and a logical operator to know when this happens. Add it to stocks as the column, ibm_buy.
If panera crosses above 213, sell. Use a logical operator to know when this happens. Add it to stocks as the column, panera_sell.
Is ibm ever above panera? Add the result to stocks as the column, ibm_vs_panera.
Print stocks.

Exercício interativo prático

Experimente este exercício completando este código de exemplo.

# Print stocks
___

# IBM range
___$___ <- 

# Panera range
___$___ <- 

# IBM vs Panera
___$___ <- 

# Print stocks
___

Editar e executar o código

Este exercício faz parte do curso

Intermediate R for Finance

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Exercise 1: Relational operators Exercise 2: Relational practice Exercise 3: Vectorized operations

Exercício atual

Exercise 4: Logical operators Exercise 5: And / Or Exercise 6: Not!Exercise 7: Logicals and subset()Exercise 8: All together now!Exercise 9: If statements Exercise 10: If this Exercise 11: If this, Else that Exercise 12: If this, Else If that, Else that other thing Exercise 13: Can you If inside an If?Exercise 14: ifelse()

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