matlab和Python线性规划

先说matlab&＃xff0c;数据用csv文件&＃xff0c;

打开数据

用csvread函数

注意&＃xff1a;csvread函数只试用与用逗号分隔的纯数字文件

第一种&＃xff1a;M &＃61; CSVREAD(‘FILENAME’) &＃xff0c;直接读取csv文件的数据&＃xff0c;并返回给M

第二种&＃xff1a;M &＃61; CSVREAD(‘FILENAME’,R,C) &＃xff0c;读取csv文件中从第R-1行&＃xff0c;第C-1列的数据开始的数据&＃xff0c;这对带有头文件说明的csv文件(如示波器等采集的文件)的读取是很重要的。

第三种&＃xff1a;M &＃61; CSVREAD(‘FILENAME’,R,C,RNG)&＃xff0c;其中 RNG &＃61; [R1 C1 R2 C2]&＃xff0c;读取左上角为索引为(R1,C1) ,右下角索引为(R2,C2)的矩阵中的数据。

注意&＃xff1a;matlab认为CSV第1行第1列的单元格坐标为&＃xff08;0,0&＃xff09;

例1.1 读取整个文件
csvread(‘csvlist.csv’)
例1.2 读取第2行以下&＃xff0c;第0列以右区域的数据
m &＃61; csvread(‘csvlist.dat’, 2, 0)
例1.3 读取第2行以下&＃xff0c;第0列以右&＃xff0c;第3行以上&＃xff0c;第3列以左区域的数据
m &＃61; csvread(‘csvlist.dat’, 2, 0, [2,0,3,3])

使用textscan函数

在使用textscan函数前必须用fopen函数打开CSV文件。textscan函数读取的结果会存在cell数组中。
help textscan
可以知道该函数可以通过控制参数&＃xff0c;从文本文件或字符串文件中读取数据
C &＃61; textscan(FID,’FORMAT’) reads data from an open text file identified by FID into cell array C. Use FOPEN to open the file and obtain FID. The FORMAT is a string of conversion specifiers enclosed in single quotation marks&＃xff08;由单括号括起来的一串字符说明&＃xff09;. The number of specifiers determines the number of cells in the cell array C. &＃xff08;说明字符的数量决定了输出cell的数量&＃xff09;For more information, see “Format Options.”

C &＃61; textscan ( FID, ‘FORMAT’ ,N) reads data from the file, using the FORMAT N times, where N is a positive integer. To read additional data from
the file after N cycles, call textscan again using the original FID.

C &＃61; textscan (FID, ‘FORMAT’, ‘PARAM’, VALUE) accepts one or more comma-separated parameter name/value pairs. For a list of parameters and values, see “Parameter Options.”

C &＃61; textscan(FID,’FORMAT’,N,’PARAM’,VALUE) reads data from the file, using the FORMAT N times, and using settings specified by pairs of PARAM/VALUE arguments.

C &＃61; textscan(STR,…) reads data from string STR. You can use the FORMAT, N, and PARAM/VALUE arguments described above with this syntax. However, for strings, repeated calls to textscan restart the scan from the beginning each time.&＃xff08;重复调用时每次从文件首部开始&＃xff09; (To restart a scan from the last position, request a POSITION output. See also Example 3.)

[C, POSITION] &＃61; textscan(…) returns the file or string position at the end of the scan as the second output argument. For a file, this is the value that FTELL(FID) would return after calling textscan&＃xff08;将读取位置作为第二个参数输出&＃xff09;. For a string, POSITION indicates how many characters textscan read.&＃xff08;对于字符串而言&＃xff0c;位置参数显示了以读取的字符数&＃xff09;

Supported values for SPECIFIER:

Numeric Input Type Specifier Output Class------------------ --------- ------------Integer, signed %d int32%d8 int8%d16 int16%d32 int32%d64 int64Integer, unsigned %u uint32%u8 uint8%u16 uint16%u32 uint32%u64 uint64Floating-point number %f double%f32 single%f64 double%n double


其他格式可以看帮助文档
Examples:

Example 1: Read each column of a text file.Suppose the text file &＃39;mydata.dat&＃39; contains the following:Sally Level1 12.34 45 1.23e10 inf Nan Yes 5.1&＃43;3iJoe Level2 23.54 60 9e19 -inf 0.001 No 2.2-.5iBill Level3 34.90 12 2e5 10 100 No 3.1&＃43;.1iRead the file:fid &＃61; fopen(&＃39;mydata.dat&＃39;);C &＃61; textscan(fid, &＃39;%s%s%f32%d8%u%f%f%s%f&＃39;);fclose(fid);textscan returns a 1-by-9 cell array C with the following cells:C{1} &＃61; {&＃39;Sally&＃39;,&＃39;Joe&＃39;,&＃39;Bill&＃39;} %class cellC{2} &＃61; {&＃39;Level1&＃39;; &＃39;Level2&＃39;; &＃39;Level3&＃39;} %class cellC{3} &＃61; [12.34;23.54;34.9] %class singleC{4} &＃61; [45;60;12] %class int8C{5} &＃61; [4294967295; 4294967295; 200000] %class uint32C{6} &＃61; [Inf;-Inf;10] %class doubleC{7} &＃61; [NaN;0.001;100] %class double C{8} &＃61; {&＃39;Yes&＃39;,&＃39;No&＃39;,&＃39;No&＃39;} %class cellC{9} &＃61; [5.1&＃43;3.0i; 2.2-0.5i; 3.1&＃43;0.1i] %class double


感谢&＃xff1a;http://blog.sina.com.cn/s/blog_a0246c110101v1k3.html

拟合

cftool

可以进行拟合&＃xff0c;很方便的看到拟合效果
1. 右键还能一键保存在底部的table of fits 中选中行右键&＃xff0c;save … to Workspace
2. 也可以生成M文件&＃xff0c;函数输出fitresult&＃xff0c;和gofl两个量。其中fitresult为函数拟合的变量结果&＃xff0c;用fitresult.参数名就可以查看参数。
3. 比如你想模拟 y &＃61; p&＃xff08;1&＃xff09;*x &＃43; p&＃xff08;2&＃xff09;&＃xff1b;
通过lsqcurvefit函数得到了 p&＃xff08;1&＃xff09;和p&＃xff08;2&＃xff09;&＃xff1b;
你把方程右边变成字符串类型: str &＃61; [num2str(p(1)),’*x&＃43;’,num2str(p(2))];
然后global y&＃xff1b; y &＃61; inline&＃xff08;str&＃xff09;&＃xff1b;
然后再另一个控件的callback中&＃xff0c;global y&＃xff1b; 假设自变量x&＃61;1&＃xff0c;输入y&＃xff08;1&＃xff09;就会得到因变量y的值

命令行调用

fit:用曲线或曲面拟合数据
fitobject &＃61; fit(x,y,fitType)按fittype说明的参数对x,y进行拟合
fitobject &＃61; fit([x,y],z,fitType)三元
fitobject &＃61; fit(x,y,fitType,fitOptions)按fitoptions设置的参数用fittype对xy进行拟合
fitobject &＃61; fit(x,y,fitType,Name,Value)
[fitobject,gof] &＃61; fit(x,y,fitType)
[fitobject,gof,output] &＃61; fit(x,y,fitType)

感谢&＃xff1a;http://cn.mathworks.com/help/curvefit/fit.html?s_tid&＃61;gn_loc_drop