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2012-10-18 19:18:16
原文地址:matlab读取excel文件及其数据处理 作者:hdu_song
在许多时候我们要借助于matlab读取excel的内容进行处理,以下是一种常用的处理方法
office的表格文件也就是xls文件本质上就是一个二维矩阵,二维矩阵是用来保存数据的最佳方式,所以在日常工作中,我们从其它地方获取的数据通常都被保存为xls格式,但处理数据时,我们却需要把xls文件的数据导入到matlab里进行处理。
如果你只处理一个文件并且只做一次的话,你可以手动来拷贝粘贴,这花费不了你太多时间。如果有很多xls文件,或者你的xls文件的内容可能随时被修改,那么下面的方法可以派上用场。
matlab自身提供了大量的函数,包括读取office文件。其中xlsread和xlswrite就是专门用来读取xls文件里的数据的。这两个函数的使用方法可以直接查看matlab自带的帮助。
xlsread对于纯数据的xls文件支持很完美,也就是说当xls文件里的每个格子都是“数”时,xlsread会直接返回一个实数矩阵。但是通 常我们拿到xls文件并不是这样,它的表头多半是描述性文字,它的数据也有可能是文字,有些位置的数据还有可能是缺失的。xlsread对这样的文件读取 无能为力,或者说需要大量的时间去协调数据的位置信息。要是有一个函数,能够按照原有的顺序直接读取所有的单位格数据就好了。当然,这时候返回的矩阵就不能是一个数值矩阵了,它将会是一个cell矩阵,里面的每个元素类型可能不一样。
matlab本身并不提供这个功能,但是另外有一个函数officedoc完美的实现这个功能。这个函数包可以去上去下载,解压缩后放到工作路径上即可。使用方法可以查询help officedoc。officedoc是收费函数包,但有免费版本,而且其免费版本可以实现上面我们所说的效果(收费版本主要是可以用来修改office文件)。
例子:
在matlab中读取xls格式的文件内容如应用如下函数:
1.bb=xlsread('c:feature.xls','a0:an40'),其中:c:feature.xls为文件存放的地址,a0:a40为将要读取的单元格的范围.bb为读取的矩阵在MATLAB中的变量名.
2.使用m文件脚本如下:
Excel = actxserver('Excel.Application');
set(Excel, 'Visible', 1);
Workbooks = Excel.Workbooks;
Workbook = invoke(Workbooks, 'Open', [cd,'\feature\ABC.xls']);
%% 读取 ABC.xls:sheet1 a1(即 R1C1)~an40(即 R240c40) 范围内的 40by40 矩阵
read_excel=ddeinit('excel','ABC.xls:sheet1');
feature1 = ddereq(read_excel, 'R1c1:R40c40');
feature1
%% 关闭ABC.xls
invoke(Excel, 'Quit');
delete(Excel);
注意:在使用时将m文件与xls文件存于同一个目录下.另外:sheet1:可以重命名,且读取sheet的名称要和实际存放的名称相同.
matlab读取excel,txt文件函数
注意matlab不识别中文,读写的文件中最好不含有中文
excel读取函数 xlsread
text 读取函数csvread
XLSREAD Get data and text from a spreadsheet in an Excel workbook.
[NUMERIC,TXT,RAW]=XLSREAD(FILE) reads the data specified in the Excel
file, FILE. The numeric cells in FILE are returned in NUMERIC, the text
cells in FILE are returned in TXT, while the raw, unprocessed cell
content is returned in RAW.
[NUMERIC,TXT,RAW]=XLSREAD(FILE,SHEET,RANGE) reads the data specified
in RANGE from the worksheet SHEET, in the Excel file specified in FILE.
It is possible to select the range of data interactively (see Examples
below). Please note that the full functionality of XLSREAD depends on
the ability to start Excel as a COM server from MATLAB.
[NUMERIC,TXT,RAW]=XLSREAD(FILE,SHEET,RANGE,'basic') reads an XLS file as
above, using basic input mode. This is the mode used on UNIX platforms
as well as on when Excel is not available as a COM server.
In this mode, XLSREAD does not use Excel as a COM server, which limits
import ability. Without Excel as a COM server, RANGE will be ignored
and, consequently, the whole active range of a sheet will be imported.
Also, in basic mode, SHEET is case-sensitive and must be a string.
[NUMERIC,TXT,RAW]=XLSREAD(FILE,SHEET,RANGE,'',CUSTOMFUN)
[NUMERIC,TXT,RAW,CUSTOMOUTPUT]=XLSREAD(FILE,SHEET,RANGE,'',CUSTOMFUN)
When the Excel COM server is used, allows passing in a handle to a
custom function. This function will be called just before retrieving
the actual data from Excel. It must take an Excel Range object (e.g. of
type 'Interface.Microsoft_Excel_5.0_Object_Library.Range') as input,
and return one as output. Optionally, this custom function may return
a second output argument, which will be returned from XLSREAD as the
fourth output argument, CUSTOMOUTPUT. For details of what is possible
using the EXCEL COM interface, please refer to Microsoft documentation.
INPUT PARAMETERS:
FILE: string defining the file to read from. Default directory is pwd.
Default extension is 'xls'.
SHEET: string defining worksheet name in workbook FILE.
double scalar defining worksheet index in workbook FILE. See
NOTE 1.
RANGE: string defining the data range in a worksheet. See NOTE 2.
MODE: string enforcing basic import mode. Valid value = 'basic'. This
is the mode always used when COM is not available (e.g. on Unix).
RETURN PARAMETERS:
NUMERIC = n x m array of type double.
TXT = r x s cell string array containing text cells in RANGE.
RAW = v x w cell array containing unprocessed numeric and text data.
Both NUMERIC and TXT are subsets of RAW.
EXAMPLES:
1. Default operation:
NUMERIC = xlsread(FILE);
[NUMERIC,TXT]=xlsread(FILE);
[NUMERIC,TXT,RAW]=xlsread(FILE);
2. Get data from the default region:
NUMERIC = xlsread('c:\matlab\work\myspreadsheet')
3. Get data from the used area in a sheet other than the first sheet:
NUMERIC = xlsread('c:\matlab\work\myspreadsheet','sheet2')
4. Get data from a named sheet:
NUMERIC = xlsread('c:\matlab\work\myspreadsheet','NBData')
5. Get data from a specified region in a sheet other than the first
sheet:
NUMERIC = xlsread('c:\matlab\work\myspreadsheet','sheet2','a2:j5')
6. Get data from a specified region in a named sheet:
NUMERIC = xlsread('c:\matlab\work\myspreadsheet','NBData','a2:j5')
7. Get data from a region in a sheet specified by index:
NUMERIC = xlsread('c:\matlab\work\myspreadsheet',2,'a2:j5')
8. Interactive region selection:
NUMERIC = xlsread('c:\matlab\work\myspreadsheet',-1);
You have to select the active region and the active sheet in the
EXCEL window that will come into focus. Click OK in the Data
Selection Dialog when you have finished selecting the active region.
9. Using the custom function:
[NUMERIC,TXT,RAW,CUSTOMOUTPUT] = xlsread('equity.xls', ..., @MyCustomFun)
Where the CustomFun is defined as:
function [DataRange, customOutput] = MyCustomFun(DataRange)
DataRange.NumberFormat = 'Date';
customOutput = 'Anything I want';
This will convert to dates all cells where that is possible.
NOTE 1: The first worksheet of the workbook is the default sheet. If
SHEET is -1, Excel comes to the foreground to enable interactive
selection (optional). In interactive mode, a dialogue will prompt
you to click the OK button in that dialogue to continue in MATLAB.
(Only supported when Excel COM server is available.)
NOTE 2: The regular form is: 'D2:F3' to select rectangular region D2:F3
in a worksheet. RANGE is not case sensitive and uses Excel A1
notation (see Excel Help). (Only supported when Excel COM server
is available.)
NOTE 3: Excel formats other than the default can also be read.
(Only supported when Excel COM server is available.)
See also xlswrite, csvread, csvwrite, dlmread, dlmwrite, textscan.
Reference page in Help browser
doc xlsread
CSVREAD Read
a comma separated value file.
M = CSVREAD('FILENAME') reads a comma separated value formatted file
FILENAME. The result is returned in M. The file can only contain
numeric values.
M = CSVREAD('FILENAME',R,C) reads data from the comma separated value
formatted file starting at row R and column C. R and C are zero-
based so that R=0 and C=0 specifies the first value in the file.
M = CSVREAD('FILENAME',R,C,RNG) reads only the range specified
by RNG = [R1 C1 R2 C2] where (R1,C1) is the upper-left corner of
the data to be read and (R2,C2) is the lower-right corner. RNG
can also be specified using spreadsheet notation as in RNG = 'A1..B7'.
CSVREAD fills empty delimited fields with zero. Data files where
the lines end with a comma will produce a result with an extra last
column filled with zeros.
See also csvwrite, dlmread, dlmwrite, load, fileformats, textscan.
Reference page in Help browser
doc csvread
Matlab如何读取Excel 表格数据
Subject:
Are there any examples that show how to use the ActiveX automation interface to connect MATLAB to Excel?
Problem Description
I am trying to control Excel from MATLAB using ActiveX. Are there any examples that show how to use the ActiveX automation interface from Excel to do this?
Solution:
Most of the functionality that you get from ActiveX is dependent on the object model, which the external application implements. Consequently, we are usually unable tp provide much information about the functions that you need to use in the remote application to perform a particular function. We do, however, have an example that shows how to do perform common functions in Excel.
We also recommend that you become more familiar with the Excel object model in order to better use Excel's ActiveX automation interface from MATLAB. You can find more information on this interface by selecting the "Microsoft Excel Visual Basic Reference" topic in the Microsoft Excel Help Topic dialog. This topic area contains a searchable description of Excel methods and properties.
The following example demonstrates how to insert MATLAB data into Excel. It also shows how to extract some data from Excel into MATLAB. For more information, refer to the individual comments for each code segment.
% Open Excel, add workbook, change active worksheet,
% get/put array, save, and close
% First open an Excel Server
Excel = actxserver('Excel.Application');
set(Excel, 'Visible', 1);
% Insert a new workbook
Workbooks = Excel.Workbooks;
Workbook = invoke(Workbooks, 'Add');
% Make the second sheet active
Sheets = Excel.ActiveWorkBook.Sheets;
sheet2 = get(Sheets, 'Item', 2);
invoke(sheet2, 'Activate');
% Get a handle to the active sheet
Activesheet = Excel.Activesheet;
% Put a MATLAB array into Excel
A = [1 2; 3 4];
ActivesheetRange = get(Activesheet,'Range','A1:B2');
set(ActivesheetRange, 'Value', A);
% Get back a range. It will be a cell array,
% since the cell range can
% contain different types of data.
Range = get(Activesheet, 'Range', 'A1:B2');
B = Range.value;
% Convert to a double matrix. The cell array must contain only scalars.
B = reshape([B{:}], size(B));
% Now save the workbook
invoke(Workbook, 'SaveAs', 'myfile.xls');
% To avoid saving the workbook and being prompted to do so,
% uncomment the following code.
% Workbook.Saved = 1;
% invoke(Workbook, 'Close');
% Quit Excel
invoke(Excel, 'Quit');
% End process
delete(Excel);
There are several options for connecting MATLAB with Excel. For an example that shows how to connect MATLAB with Excel using Excel Link, please refer to the following URL:
For an example that shows how to connect MATLAB with Excel using DDE, please refer to the following URL:
For information on how to use the XLSREAD function to read .xls files, please refer to the following URL:
在Matlab GUI中读取数据或其它文件
假设在GUI(in Matlab)中设计好一按钮,点击以后弹出对话框,并希望获取来自电脑上任一文件夹下的数据或其它文件。
做法:假设要读取在桌面上一名叫ATR_ALL.dat的数据文件,并将其值赋到Data变量,其程序代码为:
[filename, pathname] = uigetfile;
if (filename==0 & pathname==0)
msgbox('您没有选择文件,请重新选择!','打开文件出错','error');
else
NumericalDatum=load([pathname, filename]);
% NumericalDatum=xlsread([pathname, filename]);
% 然后把从计算机其它文件夹读取的数据文件保存到当前文件夹
save NumericalDatum.dat NumericalDatum -ascii;
% xlswrite('NumericalDatum.xls',NumericalDatum);
msgbox('打开及读取数据完毕!','确认','warn');
end
......
在新的应用文件中
% 最后再从当前文件夹将数据读取出来,用于当前程序
load NumericalDatum.dat;
% NumericalDatum=xlsread('NumericalDatum.xls');