How to Pass Multiple Arguments to a Function as a Single Vector

How can I pass multiple arguments to a function as a single vector?

Try this

 do.call(nDone, as.list(d))

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Explanation of what's happening in your first attempt by @joran from the comments:

R is seeing you pass a single argument to nDone, namely the vector d, which is handed off to the first function argument, under. Since you haven't specified a default value for the others, they are missing and hence the error

Apply function with multiple arguments to a vector in Julia

Use broadcast - just as you suggested in the question:

julia> f = function(a,b)
           a*b
       end
#1 (generic function with 1 method)

julia> x=[1,2,3,4,5]
5-element Vector{Int64}:
 1
 2
 3
 4
 5

julia> b=3
3

julia> f.(x, b)
5-element Vector{Int64}:
  3
  6
  9
 12
 15

map does not broadcast, so if b is a scalar you would manually need to write:

julia> map(f, x, Iterators.repeated(b, length(x)))
5-element Vector{Int64}:
  3
  6
  9
 12
 15

You can, however, pass two iterables to map without a problem:

julia> map(f, x, x)
5-element Vector{Int64}:
  1
  4
  9
 16
 25

R apply function with multiple parameters

Just pass var2 as an extra argument to one of the apply functions.

mylist <- list(a=1,b=2,c=3)
myfxn <- function(var1,var2){
  var1*var2
}
var2 <- 2

sapply(mylist,myfxn,var2=var2)

This passes the same var2 to every call of myfxn. If instead you want each call of myfxn to get the 1st/2nd/3rd/etc. element of both mylist and var2, then you're in mapply's domain.

Elegant way to pass multiple arguments to a function

If all these parameters are meaningfully related, pack them in a structure.

Passing an entire group of variables as one argument to a function C++

Write a struct with the parameters.

The multiple nested functions either need an override taking such a struct, or be rewritten to consume it as their argument.

Now you can pass parameters around in a bundle.

If the set of parameters is not uniform, you might be out of luck. You also might be able to solve it using inheritance and the like. It will depend a lot on details.

If there is a significant set of parameters that is uniform, making them a struct can reduce the number of parameters you pass around.

void do_math(int x, int y, int z, int w);

vs

struct coords {
  int x,y,z,w;
};
void do_math(coords);

if we want to keep the original do_math around we can:

inline void do_math(coords c) { do_math(c.x, c.y, c.z, c.w); }

now we can have code that wants to call do_math a bunch of times with tweaks;

void do_math_over_and_over(coords c, int x_range) {
  for(int i = 0; i < x_range; ++i) {
    coords tmp = c;
    tmp.x += i;
    do_math(tmp)
  }
}

send multiple arguments using apply function

Assuming you want to pass the row, and a single argument that is the same for each row:

manydo3 <- function(x, r1) NULL
apply(eq, 1, manydo3, r1=18)

If you want different values for the second argument for each row, then you want to split your matrix into rows and pass both the rows and your other argument with mapply:

mapply(manydo3, split(eq, row(eq)), R)

where length(R) == nrow(eq) (i.e. R contains r1, r2, etc).

How to use a vector as argument of a function with multiple parameters in r

You can use the sapply() inside your function

fun1 <- function (a, b, c, d) {    
  sapply(d, function(x) { sum (( a - x ) * b / c ) })
} 

fun1(df$a, df$b, nrow(df), c(1:3)) 
# [1] 2696.223 2643.748 2591.273

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