Handling exceptions and error messages

Whenever you are creating a function, there could be a conditional statement or even some mathematical operation that might not be executable for all situations. For example, if you are transforming a numeric vector into logarithms, then a negative value will give an error. In this recipe, you will learn how to handle exceptions and errors and/or warnings while you write your own customized functions. There are several functions in R to handle exceptions/errors/warnings as follows:

• warning(): This function can generate a warning message
• stop(): This function can generate an error message
• supressWarnings(expr): This function evaluates the expression inside the function and then ignores warnings if there are any
• tryCatch(): This function (tryCatch() or try()) evaluates the code inside the parenthesis and then assigns an exception handler

In this recipe, you will learn how to use an exception handler by creating your function.

Getting ready

Suppose you are transforming...