matlab - csvread在MATLAB中删除行

Question

我在5列中创建了一些随机数据，并将其存储为CSV文件。这个工作正常，我的CSV实际上包含1001行；我的数据带有标题(我通过在电子表格编辑器中打开它进行了检查)。但是，当我再次使用csvread在MATLAB中读取它时，如果我未指定定界符，并且当我指定定界符data仅包含957行时，则会出现错误，因此 header 和前42行丢失。这里发生了什么？

码:

A = rand(1e3,5);
out = fopen('output.csv','w');
fprintf(out,['ColumnA', ',', 'ColumnB', ',', 'ColumnC',  ',', 'ColumnD',  ',', 'ColumnE','\n']);
fclose(out);
dlmwrite('output.csv', A, 'delimiter',',','-append');
data = csvread('output.csv',',');

错误:

Error using dlmread (line 139) Mismatch between file and format string. Trouble reading number from file (row 1u, field 1u) ==> ColumnA,ColumnB,ColumnC,ColumnD,ColumnE\n

Error in csvread (line 48) m=dlmread(filename, ',', r, c);

我在写或读文件时是否缺少一些愚蠢的东西？

我在64位Windows 7计算机上运行MATLAB R2012a。 (尽管我希望在下个月升级到R2015b)

Answer 1

原因是您使用了无效的csvread语法。从help csvread:

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'.

您无法告诉 csvread使用什么定界符。当您以这种方式调用它时，它将 '解释为数字44(以ascii表示)，并将其用作起始行。

改称这个: data = csvread('output.csv',1);