Let's say I have data in a csv file [1 2 3 4 5; 6 7 8 9 10;11 12 13 14 15] Let's say I don't want the first or last columns or the first row in the data. How do I selectively draw that with csvread()?
I've tried tinkering around with setting boundaries, but csv seems to only allow a start point, from which it will draw to row/column infinity.
The ideal results would be somehow getting a matrix that is [2,3,4;7,8,9;12,13,14]
2 Answers
The documentation for csvread is accurate but confusing and somewhat non-standard for matlab. The basic syntax is:
a = csvread(filename) And if you want to specify a range, you can use:
a = csvread(filename,R1,C1,[R1 C1 R2 C2]) where the R and C are the rows and columns of interest. The trick is that the row and column values are zero-indexed, which is unusual in matlab. Also note that if you are specifying a range for reading, the first components of the array argument are the same as the other arguments.
For example, consider a file "test.csv" that looks like:
1,2,3,4 1,2,3,4 1,2,3,4 1,2,3,4 The basic read operation is:
>> a = csvread('testcsv.csv') a = 1 2 3 4 1 2 3 4 1 2 3 4 1 2 3 4 If you want to start reading at column 2, specify row 0 and column 1:
>> a = csvread('testcsv.csv',0,1) a = 2 3 4 2 3 4 2 3 4 2 3 4 And if you want to stop after column 3 while including all rows (i.e. up to row 4):
>> a = csvread('testcsv.csv',0,1,[0 1 3 2]) a = 2 3 2 3 2 3 2 3 In your specific case:
>> a = csvread('testcsv2.csv') a = 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 >> a = csvread('testcsv2.csv',1,1,[1 1 2 3]) a = 7 8 9 12 13 14 Please refer to this documentation on csvread :
In the page, you can see various implementations of csvread() such as
M = csvread(filename,R1,C1) where R1 is the row offset and C1 is the column offset. You can probably try your way around with this and solve your problem.
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