Returns a list filled with zeroes.

newList(*length*)

**Menu Location**

This command can't be found in any menu besides the command catalog.

This command works on all calculators.

1 byte

The `newList()` command returns a list of a specific length that is filled entirely with zeroes.

```
:newList(3)
{0 0 0}
:newList(5)
{0 0 0 0 0}
:newList(0)
{}
```

This can be easily expanded to returning a list filled with any value: to return a list filled with a value x, just add x to the result of `newList()`. This works for strings as well, since "Hello"+0 simplifies to "Hello".

# Advanced Uses

`newList()` can be used for making a comparison between a single value and a list. Normally, something like {1,2,3,4}=2 simply returns "false", since 2 is not a list and {1,2,3,4} is. To do a comparison element-by-element, use `newList()` to turn the single value into a list: in this case, 2+`newList(4)`. Comparing {1,2,3,4} to 2+`newList(4)` will return {false, true, false, false} (you might use `when()` to get a single value out of this list).

This works to extend other operations to a number and a list, as well, though comparisons are the most useful application of this technique, since most operations already work this way.

# Optimization

In many cases, an expression with `newList()` can be used to optimize a `seq()` command. First, observe that the simple

`:seq(k,k,1,n)`

which will return the list {1,2,3,…,n}, can be replaced by

`:cumSum(1+newList(n))`

The result is about twice as fast.

This is useful because many `seq()` expressions can be expressed using something like `seq(k,k,1,n)`. For example:

```
:seq(k^2,k,1,n)
can be
:seq(k,k,1,n)^2
which is
:cumSum(1+newList(n))^2
```

This rearrangement is not always possible, but when it is, it gives a significant improvement in speed, with no real difference in size.

Here is a more complicated example (which is a sequence of probabilities with the binomial distribution). Notice the use of the `with` operator.

```
:seq(nCr(n,k) p^k (1-p)^(n-k),k,1,n)
can be
:nCr(n,a) p^a (1-p)^(n-a)|a=cumSum(1+newList(n))
```

# Error Conditions

**260 - Domain error** happens when the length is not an integer ≥0.