# Documentation

### This is machine translation

Translated by
Mouseover text to see original. Click the button below to return to the English verison of the page.

Note: This page has been translated by MathWorks. Please click here
To view all translated materals including this page, select Japan from the country navigator on the bottom of this page.

# startsWith

Determine if string starts with pattern

## Syntax

``TF = startsWith(str,pattern)``
``TF = startsWith(str,pattern,'IgnoreCase',true)``

## Description

example

````TF = startsWith(str,pattern)` returns `1` (`true`) if `str` starts with the specified pattern, and returns `0` (`false`) otherwise.If `pattern` is an array containing multiple patterns, then `startsWith` returns `1` if it finds that `str` starts with any element of `pattern`.```

example

````TF = startsWith(str,pattern,'IgnoreCase',true)` ignores case when determining if `str` starts with `pattern`. ```

## Examples

collapse all

Create a string array that contains file names. Determine which file names start with the word `data`.

Starting in R2017a, you can create strings using double quotes instead of the `string` function.

```str = ["abstract.docx","data.tar","code.m"; ... "data-analysis.ppt","results.ptx","summary.ppt"]```
```str = 2x3 string array "abstract.docx" "data.tar" "code.m" "data-analysis.ppt" "results.ptx" "summary.ppt" ```

Return a logical array where the position of each element equal to `1` corresponds to the position of a string in `str` that starts with `data`.

```pattern = "data"; TF = startsWith(str,pattern)```
```TF = 2x3 logical array 0 1 0 1 0 0 ```

Display the file names that start with `data`. Index back into `str` using `TF`.

`str(TF)`
```ans = 2x1 string array "data-analysis.ppt" "data.tar" ```

Create a string array that contains file names. Determine which file names start with either `abstract` or `data`.

Starting in R2017a, you can create strings using double quotes instead of the `string` function.

`str = ["abstract.docx","data.tar.gz","mycode.m","results.ptx"]`
```str = 1x4 string array "abstract.docx" "data.tar.gz" "mycode.m" "results.ptx" ```
```pattern = ["abstract","data"]; TF = startsWith(str,pattern)```
```TF = 1x4 logical array 1 1 0 0 ```

Display the strings that start with either `abstract` or `data`. Index back into `str` using `TF`.

`str(TF)`
```ans = 1x2 string array "abstract.docx" "data.tar.gz" ```

Create a string array that contains file names. Determine which file names start with `data`, ignoring case.

Starting in R2017a, you can create strings using double quotes instead of the `string` function.

`str = ["DATA.TAR.GZ","data.xlsx","SUMMARY.PPT","tmp.gz"]`
```str = 1x4 string array "DATA.TAR.GZ" "data.xlsx" "SUMMARY.PPT" "tmp.gz" ```
```pattern = "data"; TF = startsWith(str,pattern,'IgnoreCase',true)```
```TF = 1x4 logical array 1 1 0 0 ```

Display the strings that start with `data`. Index back into `str` using `TF`.

`str(TF)`
```ans = 1x2 string array "DATA.TAR.GZ" "data.xlsx" ```

Create a character vector that contains the name of a file. Determine if the name starts with different patterns.

`chr = 'data-analysis.ppt'`
```chr = 'data-analysis.ppt' ```
`TF = startsWith(chr,'data')`
```TF = logical 1 ```
`TF = startsWith(chr,'test')`
```TF = logical 0 ```

## Input Arguments

collapse all

Input string.

Data Types: `string` | `char` | `cell`

Search pattern, specified as a string array, a character vector, or a cell array of character vectors.

Data Types: `string` | `char` | `cell`

## See Also

### Topics

#### Introduced in R2016b

Was this topic helpful?

#### Beyond Excel: The Manager's Guide to Solving the Big Data Conundrum

Download white paper