apply does not result in the same vector like replaced for

the function "trio" exemplifies a function with numerous calculations, that takes in certain columns from a data frame (df) and three values for the calculations:

# example: data
df <- data.frame(C1= c(1,2,3,4,5,6),C2= c(5,4,3,2,1,6),C3= c(9,1,5,2,7,4))

# example: function
trio  <- function(a,b,c){
             df2 <- df %>%
             mutate(., 
                 df$C1 * a,
                 df$C2 * b,
                 df$C2 * c 
              ) 
df2$calc <- df2[3] * df2[4]/df2[5]
max(df2$calc)
}

to find which value combination results in the best output (= max(df2$calc) a matrix with value combinations is created:

pp <- expand.grid(parameter_A = round(seq(min, max, length.out = count),3),
                  parameter_B = round(seq(min, max, length.out = count),3), 
                  parameter_C = round(seq(min, max, length.out = count),3))

To replace the for loop

max.all<- c()
for(w in 1:nrow(pp)){
    max.all[w] <-  findWinZ(pp[w,1],pp[w,2],pp[w,3])  
    }

I aimed to use one function of the Apply-Family (sapply, lapply), eg

Version1: res2 <- sapply(pp, function(a,b,c)  findWinZ(length(pp[,1]),length(pp[,2]),length(pp[,3])))  

Version: res3 <- sapply(pp, function(a,b,c)  length(findWinZ(pp[w,1],pp[w,2],pp[w,3])))  

Alas, the outcome of the apply() loops is wrong. What I need is the vector with all results, ie the same output as I get from the for loop. Please, can anyone correct my apply() code? Thanks a lot!

---

如果问题是如何将for循环重写为sapply，那么：

res4 <- sapply(1:nrow(pp), function(w) findWinZ(pp[w,1],pp[w,2],pp[w,3]))

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