fix error: Error in newDist$sample$(10^5)$ :

Result of formula evaluation is not numeric.

Execution halted

in code:

# Define the randomVariate class

randomVariate $<-$ function$($distFormula$,$ defs$)\{$

# Validate input arguments

stopifnot$($is$.$list$($defs$))$

# Define the S$3$ class object

dist $<-$ list$($formula $=$ distFormula, definitions $=$ defs$)$

dist$sample $<-$ function$($n$)\{$

# Evaluate the formula using the provided definitions

result $<-$ sapply$(1$:n$,$ function$($i$)$ eval$($dist$formula, envir $=$ list$($x $=$ defs$x$[$i$]),$ enclos $=$ parent.frame$()))$

# Ensure the result is a numeric vector

if $(!$is$.$numeric$($result$))\{$

stop$("$Result of formula evaluation is not numeric."$)$

$\}$

return$($result$)$

$\}$

# Define the print method

print.randomVariate $<-$ function$($obj$)\{$

cat$("$Formula:$",$ as$.$character$($obj$formula$),"$

Definitions:

$")$

for $($key in names$($obj$definitions$))\{$

cat$($key$,"$:$",$ as$.$character$($obj$definitions$[[$key$]]),"$

$")$

$\}$

$\}$

# Return the object

class$($dist$)<-$ c$("$randomVariate$",$ "function"$)$

return$($dist$)$

$\}$

# Example usage

# Define a new random variable

newDist $<-$ randomVariate$($distFormula $=$ ~x$^2,$ defs $=$ list$($x $=$ rnorm$(10^5)))$

# Generate a random sample

sample$1<-$ newDist$sample$(10^5)$

# Plot a histogram

hist$($sample$1,$ breaks $=$ "Scott", probability $=$ TRUE, col $=$ rgb$(1,0,1,0\mathrm{.}2),$ density $=20,$ angle $=45)$

lines$($density$($sample$1,$ adjust $=5),$ col $=$ rgb$(1,0,1,1))$