Importing and Exporting Data (Development Environment)

Development Environment

Using Import Functions with Binary Data

To import binary data from the command line or in an M-file, you must use one of the MATLAB import functions. Your choice of function depends on how the data in the text file is formatted.

To find the function designed to work with a particular binary data format, scan the data formats listed in Table 6-5. The table lists the binary formats and the MATLAB high-level functions you use to import them, along with pointers to additional information. To view the alphabetical list of MATLAB binary data export functions, see Table 6-6.

Note If MATLAB does not support a high-level function that works with a particular binary data format, use the MATLAB low-level file I/O functions to import the data. You must know how the binary data is formatted in the file. See Using Low-Level File I/O Functions for more information.

Data Format	File Extension	Function
Audio files	`.au` `.wav`	`auread` (on Sun systems) `wavread` (on Microsoft Windows systems)
Audio-video Interleaved (AVI)	`.avi`	`aviread`
Band-interleaved data	No standard file extension	`multibandread`
Common Data Format (HDF)	`.cdf`	`cdfread`
Hierarchical Data Format (HDF)	`.hdf`	`imread` `Use imread only f`or HDF raster image files. For all other HDF files, see Importing HDF Data for complete information.
Image files	`.bmp .cur .gif .hdf .ico .jpg (.jpeg) .pbm .pcx .pgm .png .pnm .ppm .ras .tif (.tiff) .xwd`	`imread`
MATLAB proprietary format (MAT-files)	`.mat`	`load` See Loading a Saved Workspace and Importing Data for more information.
Spreadsheets (Excel or Lotus 123)	`.xls .wk1`	`xlsread`

Function	File Extension	Data Format
`auread`	`.au`	Import sound data in Sun Microsystems format.
`aviread`	`.avi`	Import audio-visual data in AVI format.
`cdfread`	`.cdf`	Import Common Data Format (CDF) data.
`hdf`	`.hdf`	Import data in Hierarchical Data Format (HDF). For HDF image file formats, use `imread`. For all other HDF files, see Importing HDF Data for complete information.
`imread`	`.bmp .cur .gif .hdf .ico .jpg (.jpeg) .pbm .pcx .pgm .png .pnm .ppm .ras .tif (.tiff) .xwd`	Import images in many formats.
`load`	`.mat`	Import MATLAB workspace variables in MAT-files format.
`multibandread`	No standard file extension	Import three-dimensional, band-interleaved data.
`wavread`	`.wav`	Import sound data in Microsoft Windows format.
`wk1read`	`.wk1`	Import data in Lotus 123 spreadsheet format.
`xlsread`	`.xls`	Import data in Microsoft Excel spreadsheet format.

Table 6-5: Binary Data Formats and MATLAB Import Functions

Data Format
File Extension
Function

Audio files
.au
.wav
auread (on Sun systems)
wavread (on Microsoft Windows systems)

Audio-video Interleaved (AVI)
.avi
aviread

Band-interleaved data
No standard file extension
multibandread

Common Data Format (HDF)
.cdf
cdfread

Hierarchical Data Format (HDF)
.hdf
imread
Use imread only for HDF raster image files. For all other HDF files, see Importing HDF Data for complete information.

Image files
.bmp .cur .gif .hdf .ico .jpg (.jpeg) .pbm .pcx .pgm .png .pnm .ppm .ras .tif (.tiff) .xwd
imread

MATLAB proprietary format (MAT-files)
.mat
load
See Loading a Saved Workspace and Importing Data for more information.

Spreadsheets (Excel or Lotus 123)
.xls .wk1
xlsread

Table 6-6: Binary Data Import Functions

Function
File Extension
Data Format

auread
.au
Import sound data in Sun Microsystems format.

aviread
.avi
Import audio-visual data in AVI format.

cdfread
.cdf
Import Common Data Format (CDF) data.

hdf
.hdf
Import data in Hierarchical Data Format (HDF). For HDF image file formats, use imread. For all other HDF files, see Importing HDF Data for complete information.

imread
.bmp .cur .gif .hdf .ico .jpg (.jpeg) .pbm .pcx .pgm .png .pnm .ppm .ras .tif (.tiff) .xwd
Import images in many formats.

load
.mat
Import MATLAB workspace variables in MAT-files format.

multibandread
No standard file extension
Import three-dimensional, band-interleaved data.

wavread
.wav
Import sound data in Microsoft Windows format.

wk1read
.wk1
Import data in Lotus 123 spreadsheet format.

xlsread
.xls
Import data in Microsoft Excel spreadsheet format.

Using the Import Wizard with Binary Data Files Exporting Binary Data