用load函数导入mat文件大家都会。但是今天我拿到一个数据，文件后缀名居然是‘.data’。该怎么读呢？
我只好用matlab界面Workspace区域的“import data”按钮手工导入该文件。恩，还好，居然成功了。顺便提一下，这个“import data”按钮功能很强大，连excel文件都能导入。
但是如果在脚本里如何导入这种非mat文件呢？
这时候就轮到“importdata”函数登场啦！
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importdata
Load data from file
Syntax
importdata(filename)
A = importdata(filename)
A = importdata(filename, delimiter)
A = importdata(filename, delimiter, nheaderlines)
[A, delimiter] = importdata(...)
[A, delimiter, nheaderlines] = importdata(...)
[...] = importdata('-pastespecial', ...)
Description
importdata(filename) loads data from filename into the workspace.
A = importdata(filename) loads data into A.
A = importdata(filename, delimiter) interprets delimiter as the column separator in ASCII file filename.
A = importdata(filename, delimiter, nheaderlines) loads data from ASCII file filename, reading numeric data starting from line nheaderlines+1.
[A, delimiter] = importdata(...) returns the detected delimiter character for the input ASCII file.
[A, delimiter, nheaderlines] = importdata(...) returns the detected number of header lines in the input ASCII file.
[...] = importdata('-pastespecial', ...) loads data from the system clipboard rather than from a file.
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这个函数可以支持的文件格式有：MAT文件，ASCII files和Spreadsheets，images, Audio files
这个ASCII files和Spreadsheets指的是：For ASCII files, data contains a double array. Other fields contain cell arrays.
For spreadsheets, each field contains a struct, with one field for each worksheet.