isfile

Determine if input is file

Syntax

result = isfile(filename)

Description

result = isfile(filename) returns logical 1 (true) if filename is a file located on the specified path or in the current folder. Otherwise, isfile returns logical 0 (false).

Examples

Is Input a File

Check if the input myfile1.txt is a file. A result of 1 indicates that myfile1.txt is a file.

result = isfile('myfile1.txt')

result = logical
   1

Create the folder myfolder, then check if myfolder is a file. A result of 0 indicates that myfolder is not a file.

mkdir myfolder;
result = isfile('myfolder')

result = logical
   0

Check if the inputs myfile1.txt and myfolder are files. A result of [1 0] indicates that myfile1.txt is a file and myfolder is not a file.

result = isfile(["myfile1.txt", "myfolder"])

result = 1×2 logical array
   1   0

Input Arguments

filename — Filename

string array | character vector | cell array of character vector

Filename, specified as a string array, character vector, or cell array of character vectors. For a local file, filename can include a relative path, but the relative path must be in the current folder. Otherwise, filename must include a full path.

For files and folders at a remote location, you must specify the full path as a uniform resource locator (URL). Internet URLs must include the protocol type "http://" or "https://". For more information, see Work with Remote Data.

Limitations

• MATLAB^® does not support internet URLs that require authentication.

• For remote locations with authentication, isfile will only interpret the first location (which may be the authentication page) and ignore redirects.

• MATLAB Online™ supports internet URLs associated with Microsoft^® OneDrive™ files and folders, while the installed version of MATLAB supports only local OneDrive files.

Extended Capabilities

C/C++ Code Generation

Generate C and C++ code using MATLAB® Coder™.

Usage notes and limitations:

• Use of file: in the specified path is not supported.

• No preprocessing is applied on the specified path.

• In certain cases, the behavior of the generated code might differ from MATLAB. In such cases, the behavior of the generated C code matches that of stat on UNIX^® and GetFileAttributesA on Windows^®.

GPU Code Generation

Generate CUDA® code for NVIDIA® GPUs using GPU Coder™.

Refer to the usage notes and limitations in the C/C++ Code Generation section. The same usage notes and limitations apply to GPU code generation.

Thread-Based Environment

Run code in the background using MATLAB® backgroundPool or accelerate code with Parallel Computing Toolbox™ ThreadPool.

The isfile function fully supports thread-based environments. For more information, see Run MATLAB Functions in Thread-Based Environment.

Version History

Introduced in R2017b

R2024b: Read data over HTTP and HTTPS using file operation functions

You can read data from primary online sources by performing file read operations over an internet URL.