non-numeric argument to function

This error message typically occurs when a function is expecting a numeric input (such as a number or vector) but is instead given a non-numeric input (such as a character string or logical value).

For example, if you try to calculate the square root of a character string using the sqrt() function in R, you will get this error message because the function is expecting a numeric input:

sqrt("hello")
Error in sqrt("hello") : non-numeric argument to mathematical function

To fix this error, make sure that you are passing a numeric input to the function. Check that all the values you are using as input are numeric and not accidentally coded as character strings or other non-numeric types.