Matlab數(shù)據(jù)的導(dǎo)入與導(dǎo)出

2023/2/3數(shù)據(jù)的導(dǎo)入與導(dǎo)出2023/2/3主要內(nèi)容從TXT文件中讀取數(shù)據(jù)把數(shù)據(jù)寫(xiě)入TXT文件從Excel文件中讀取數(shù)據(jù)把數(shù)據(jù)寫(xiě)入Excel文件2023/2/3第一節(jié)從TXT文件中讀取數(shù)據(jù)MATLAB中讀取文本文件的常用函數(shù)2023/2/3一、利用數(shù)據(jù)導(dǎo)入向?qū)?dǎo)入TXT文件2023/2/3數(shù)據(jù)文件略去……【例2.1-1】利用數(shù)據(jù)導(dǎo)入向?qū)ёx取文件examp02_01.txt至examp02_11.txt中的數(shù)據(jù)2023/2/3二、調(diào)用高級(jí)函數(shù)讀取數(shù)據(jù)1.調(diào)用importdata函數(shù)讀取數(shù)據(jù)調(diào)用格式：importdata(filename)A=importdata(filename)A=importdata(filename,delimiter)A=importdata(filename,delimiter,headerline)[AD]=importdata(…)[ADH]=importdata(…)[…]=importdata(‘-pastespecial’,…)

2023/2/3>>importdata('examp02_04.txt')>>x=importdata('examp02_07.txt')>>x=importdata('examp02_03.txt',';')>>x=importdata('examp02_08.txt','',2)>>[x,s,h]=importdata('examp02_07.txt')>>FileContent=importdata('examp02_10.txt')【例2.1-2】調(diào)用importdata函數(shù)讀取文件examp02_01.txt至examp02_11.txt中的數(shù)據(jù)2023/2/32.調(diào)用load函數(shù)讀取數(shù)據(jù)調(diào)用格式：S=load(filename)S=load(filename,variables)S=load(filename,'-mat',variables)S=load(filename,'-ascii')load(...)load...2023/2/3>>loadexamp02_01.txt>>load-asciiexamp02_01.txt>>x1=load('examp02_02.txt')>>x1=load('examp02_02.txt','-ascii');>>loadexamp02_03.txt>>loadexamp02_04.txt……【例2.1-3】調(diào)用load函數(shù)讀取文件examp02_01.txt至examp02_12.txt中的數(shù)據(jù)2023/2/33.調(diào)用dlmread函數(shù)讀取數(shù)據(jù)調(diào)用格式：M=dlmread(filename)M=dlmread(filename,delimiter)M=dlmread(filename,delimiter,R,C)M=dlmread(filename,delimiter,range)2023/2/3>>x=dlmread('examp02_03.txt')>>x=dlmread('examp02_03.txt',',',2,3)>>x=dlmread('examp02_03.txt',',',[1,2,2,5])>>x=dlmread('examp02_05.txt')>>x=dlmread('examp02_06.txt')>>x=dlmread('examp02_09.txt')……【例2.1-4】調(diào)用dlmread函數(shù)讀取文件examp02_01.txt至examp02_11.txt中的數(shù)據(jù)2023/2/34.調(diào)用textread函數(shù)讀取數(shù)據(jù)調(diào)用格式：[A,B,C,…]=textread('filename','format')[A,B,C,…]=textread('filename','format',N)[…]=textread(…,'param','value',…)textread函數(shù)支持的format字符串textread函數(shù)支持的參數(shù)名與參數(shù)值列表2023/2/3>>x1=textread('examp02_01.txt');>>x2=textread('examp02_02.txt');>>x3=textread('examp02_03.txt','','delimiter',',');>>[c1,c2,c3,c4,c5]=textread('examp02_04.txt','%f%f%f%f%f','delimiter',',;*');>>x5=textread('examp02_05.txt','','emptyvalue',-1)>>x8=textread('examp02_08.txt','','headerlines',7)>>x9=textread('examp02_09.txt','','delimiter',',','whitespace','+i')>>[c1,c2,c3,c4,c5,c6,c7,c8]=textread('examp02_09.txt',...'%f%f%f%f%f%f%f%f','delimiter',',','whitespace','+i');……【例2.1-5】調(diào)用textread函數(shù)讀取文件examp02_01.txt至examp02_11.txt中的數(shù)據(jù)2023/2/3三、調(diào)用低級(jí)函數(shù)讀取數(shù)據(jù)1.調(diào)用fopen函數(shù)打開(kāi)文件調(diào)用格式：[fid,message]=fopen(filename,permission)[filename,permission]=fopen(fid)2023/2/32.調(diào)用fclose函數(shù)關(guān)閉文件調(diào)用格式：status=fclose(fid)status=fclose('all')2023/2/33.調(diào)用fseek、ftell、frewind和feof函數(shù)控制讀寫(xiě)位置調(diào)用格式：status=fseek(fid,offset,origin)%設(shè)定文件指針位置position=ftell(fid)%獲取文件指針位置frewind(fid)%移動(dòng)當(dāng)前文件指針到文件的開(kāi)頭eofstat=feof(fid)%判斷是否到達(dá)文件末尾2023/2/34.調(diào)用fgets、fgetl函數(shù)讀取文件的下一行調(diào)用格式：tline=fgets(fid)tline=fgets(fid,nchar)tline=fgetl(fid)2023/2/35.調(diào)用textscan函數(shù)讀取數(shù)據(jù)調(diào)用格式：C=textscan(fid,'format')C=textscan(fid,'format',N)C=textscan(fid,'format',param,value,…)C=textscan(fid,'format',N,param,value,…)C=textscan(str,…)[C,position]=textscan(…)2023/2/3>>fid=fopen('examp02_08.txt','r');%以只讀方式打開(kāi)文件examp02_08.txt>>fgets(fid);%讀取文件的第1行>>fgets(fid);%讀取文件的第2行>>A=textscan(fid,'%f%f%f%f%f%f','CollectOutput',1)A=[3x6double]>>fgets(fid);%讀取文件的第6行>>fgets(fid);%讀取文件的第7行>>B=textscan(fid,'%f%f%f','CollectOutput',1)B=[2x3double]>>fclose(fid);%關(guān)閉文件……【例2.1-6】調(diào)用textscan函數(shù)讀取文件examp02_01.txt至examp02_13.txt中的數(shù)據(jù)2023/2/3第二節(jié)把數(shù)據(jù)寫(xiě)入TXT文件MATLAB中寫(xiě)文本文件的常用函數(shù)2023/2/3一、調(diào)用dlmwrite函數(shù)寫(xiě)入數(shù)據(jù)調(diào)用格式：dlmwrite(filename,M)dlmwrite(filename,M,'D')dlmwrite(filename,M,'D',R,C)dlmwrite(filename,M,'attrib1',value1,'attrib2',value2,…)dlmwrite(filename,M,'-append')dlmwrite(filename,M,'-append',attribute-valuelist)dlmwrite函數(shù)支持的參數(shù)名與參數(shù)值列表2023/2/3%定義復(fù)數(shù)矩陣>>x=[1.455390+1.360686i8.692922+5.797046i5.498602+1.449548i8.530311+6.220551i3.509524+5.132495i4.018080+0.759667i2.399162+1.233189i1.839078+2.399525i4.172671+0.496544i9.027161+9.447872i4.908641+4.892526i3.377194+9.000538i];%將復(fù)數(shù)矩陣x寫(xiě)入文件examp02_09.txt，用逗號(hào)(',')作分隔符，用'\r\n'作換行符>>dlmwrite('examp02_09.txt',x,'delimiter',',','newline','pc')【例2.2-1】用逗號(hào)作為分隔符，調(diào)用dlmwrite函數(shù)將如下復(fù)數(shù)矩陣寫(xiě)入文件examp02_09.txt2023/2/3二、調(diào)用fprintf函數(shù)寫(xiě)入數(shù)據(jù)調(diào)用格式：count=fprintf(fid,format,A,…)【例】

%在屏幕上顯示一句話(huà)>>y=fprintf(1,'祝福我們偉大的新中國(guó)%d周歲生日快樂(lè)?。?！',60)祝福我們偉大的新中國(guó)60周歲生日快樂(lè)?。?！y=382023/2/3%產(chǎn)生一個(gè)8行5列的隨機(jī)矩陣，其元素服從[0,10]上的均勻分布>>x=10*rand(8,5);%以寫(xiě)入方式打開(kāi)文件，返回文件標(biāo)識(shí)符>>fid=fopen('examp02_01.txt','wt');%把矩陣x以指定格式寫(xiě)入文件examp02_01.txt>>fprintf(fid,'%-f%-f%-f%-f%-f%-f%-f%-f\n',x);>>fclose(fid);%關(guān)閉文件……【例2.2-2】用fprintf函數(shù)將數(shù)據(jù)寫(xiě)入文件examp02_01.txt至examp02_11.txt的代碼調(diào)用fprintf函數(shù)寫(xiě)入數(shù)據(jù)或在屏幕上顯示數(shù)據(jù)時(shí)，format參數(shù)指定的格式循環(huán)作用在矩陣的列上，原始矩陣的列在文件中或屏幕上就變成了行。2023/2/3第三節(jié)從Excel文件中讀取數(shù)據(jù)2023/2/3一、利用數(shù)據(jù)導(dǎo)入向?qū)?dǎo)入Excel文件2023/2/3二、調(diào)用xlsread函數(shù)讀取數(shù)據(jù)調(diào)用格式：num=xlsread(filename)num=xlsread(filename,-1)num=xlsread(filename,sheet)num=xlsread(filename,range)num=xlsread(filename,sheet,range)num=xlsread(filename,sheet,range,'basic')num=xlsread(filename,…,functionhandle)[num,txt]=xlsread(filename,…)[num,txt,raw]=xlsread(filename,…)[num,txt,raw,X]=xlsread(filename,…,functionhandle)xlsreadfilenamesheetrangebasic2023/2/3%讀取文件examp02_14.xls第1個(gè)工作表中單元格A2:H4中的數(shù)據(jù)>>num=xlsread('examp02_14.xls','A2:H4')%返回讀取的數(shù)據(jù)矩陣numnum=1601016010101NaN063632601016010102NaN073733601016010103NaN000【例2.3-1】用xlsread函數(shù)的這種調(diào)用讀取文件examp02_14.xls第1個(gè)工作表中區(qū)域A2:H4的數(shù)據(jù)2023/2/3第四節(jié)把數(shù)據(jù)寫(xiě)入Excel文件2023/2/3一、調(diào)用xlswrite函數(shù)寫(xiě)數(shù)據(jù)到Excel調(diào)用格式：xlswrite(filename,M)xlswrite(filename,M,sheet)xlswrite(filename,M,range)xlswrite(filename,M,sheet,range)status=xlswrite(filename,…)[status,message]=xlswrite(filename,…)xlswritefilenameMsheetrange2023/2/3%生成一個(gè)10行10列的隨機(jī)矩陣，其元素服從[0,1]上的均勻分布>>x=rand(10);%把矩陣x寫(xiě)入文件examp02_15.xls的第2個(gè)工作表中的單元格區(qū)域D6:M15，并返回操作信息>>[s,t]=xlswrite('examp02_15.xls',x,2,'D6:M15')s=1t=message:''identifier:''【例2.4-1】生成一個(gè)10×10的隨機(jī)數(shù)矩陣，將它寫(xiě)入Excel文件examp02_15.xls的第2個(gè)工作表的指定區(qū)域2023/2/3>