MATLAB數(shù)據(jù)導(dǎo)入與導(dǎo)出

1、MATLAB的數(shù)據(jù)導(dǎo)入與導(dǎo)出1MATLAB的數(shù)據(jù)導(dǎo)入數(shù)據(jù)的直接輸入 A=1 2 3 4 5 6；M文件中生成利用fopen，fread，和MATLAB輸入輸出函數(shù)。從ASCII文件中導(dǎo)入 利用load命令2LOAD 接受絕對或相對路徑輸入。如果文件的擴(kuò)展名不是.mat，則系統(tǒng)把文件當(dāng)作ASCII碼文件進(jìn)行處理。單獨(dú)使用時(shí)，默認(rèn)輸入的命令matlab.mat。如果找不到這個(gè)文件，則會(huì)報(bào)錯(cuò)。LOAD X loads only X.LOAD X Y Z . loads just the specified variables. The wildcard * loads variables that

2、match a pattern (MAT-).如果文件是mat文件，所需變量將在工作空間產(chǎn)生，否則，會(huì)產(chǎn)生一個(gè)雙精度矩陣，矩陣名為文件名。 S = LOAD(.) returns the contents of in variable S. If is a MAT file, S is a struct containing fields matching the variables retrieved. If is an ASCII file, S is a double precision array.3舉例load fname a* % Load variables starting w

3、ith a load fname -regexp bd3$ % Load variables starting with b and % followed by 3 digits load fname -regexp d % Load variables containing any digits4利用特定文件讀取函數(shù) dlmreadwk1readtextscantextread創(chuàng)建mex文件讀取文件創(chuàng)建其他程序文件讀取5MATLAB的數(shù)據(jù)導(dǎo)出diarysave ascii以特定格式寫入文件利用特定文件寫入程序dlmwrite作為mat文件輸出數(shù)據(jù)6MATLAB的文件操作 UIGETFILE

4、對話框打開文件方式. , PATHNAME, FILTERINDEX = UIGET, TITLE)顯示一個(gè)需要用戶完成的對話框，返回文件名，文件路徑，和是否打開成功，如果打開成功，返回成功標(biāo)志，否則會(huì)出現(xiàn)一錯(cuò)誤信息，用戶可以打開另一文件，或取消。 , pathname, filterindex = uigetfile(*.m, Pick an M-file); 7MATLAB的文件操作UIPUTFILE 對話框打開文件方式. , PATHNAME, FILTERINDEX = UIPUT, TITLE)顯示一個(gè)需要用戶完成的對話框，返回文件名，文件路徑，和是否打開成功，如果打開成功，返回成功

5、標(biāo)志，否則會(huì)出現(xiàn)一錯(cuò)誤信息，用戶可以打開另一文件，或取消。 , pathname = uiputfile(matlab.mat, Save Workspace as); 8MATLAB的文件操作 FOPEN 打開文件 可以是一個(gè)相對路徑，如果文件不在當(dāng)前目錄，系統(tǒng)將會(huì)在其他路徑進(jìn)行搜索。FID = FOPEN()FID 稱為文件標(biāo)識(shí)符，如果錯(cuò)誤，返回-1 9MATLAB的文件操作 r read w write (create if necessary) a append (create if necessary) r+ read and write (do not create) w+ tru

6、ncate or create for read and write a+ read and append (create if necessary) W write without automatic flushing A append without automatic flushing10MATLAB的文件操作Two are automatically available and need not be opened. They are FID=1 (standard output) and FID=2 (standard error).FID, MESSAGE = FOPEN() re

7、turns a system dependent error message if the open is not successful.11MATLAB的文件操作FCLOSE Close file. ST = FCLOSE(FID) closes the FID, which is an integer obtained from an earlier FOPEN. FCLOSE returns 0 if successful and -1 if not. ST = FCLOSE(a) closes all open files, except 0, 1 and 2.12MATLAB的文件操

8、作 FGETS Read line from file, keep newline character. TLINE = FGETS(FID) returns the next line of a with FID as a MATLAB string. The line terminator is included. Use FGETL to get the next line WITHOUT the line terminator. If just an end-of- encountered then -1 is returned.13MATLAB的文件操作FPRINTF Write f

9、ormatted data to file. COUNT = FPRINTF(FID,FORMAT,A,.) formats the data in the real part of array A (and in any additional array arguments), under control of the specified FORMAT string, and writes it to the file associated with FID. COUNT is the number of bytes successfully written. FID is an integer obtained from FOPEN. It can also be 1 for standard output (the screen) or 2 for standard error. If FID is omitted, output goes to