# datefind

Indices of date numbers in matrix

## Syntax

```Indices = datefind(Subset, Superset, Tolerance)
```

## Arguments

 `Subset` Subset matrix of date numbers used to find matching date numbers in `Superset`. These date numbers must be a nonrepeating subset of those in `Superset`. `Superset` Superset matrix of nonrepeating date numbers whose elements are sought. `Tolerance` (Optional) Tolerance (`+/-`) for matching the date numbers in `Superset`. A positive integer. Default = 0`.`

## Description

`Indices = datefind(Subset, Superset, Tolerance)` returns a vector of indices to the date numbers in `Superset` that are present in `Subset`, plus or minus the `Tolerance`. If no date numbers match, `Indices = []`.

Although this function was designed for use with sequential date numbers, you can use it with any nonrepeating integers.

## Examples

collapse all

### Return a Vector of Indices to Date Numbers

This example shows how to return a vector of indices to date numbers.

```Superset = datenum(1999, 7, 1:31); Subset = [datenum(1999, 7, 10); datenum(1999, 7, 20)]; Indices = datefind(Subset, Superset, 1) ```
```Indices = 9 10 11 19 20 21 ```