Re: Format of mat file

[Ian McCallion]

On Tuesday, 25 December 2018, Rich Lakey <address@hidden> wrote:
> just getting started and have
>
> M=csvread('file.csv')
>
>   and then
>
> save('file.mat','M')
>
> File looks ok but cannot find description of what it should look like. First few lines:
>
> # Created by Octave 4.2.2, Tue Dec 25 15:27:10 2018 CST <address@hidden>
> # name: M
> # type: matrix
> # rows: 1258
> # columns: 1
>  1833.3199
>  1842.02
>  1841.4
>  1841.0699
>
> The data starts in column 2 or is the first column zero?  Should my data be in the fist column? Do I reference data starting in row 1 or 6 after the header info. I'm assuming Octave skips the header info and treats row 6 as 1.

I can't see why you need to know the format of the file. Save data, then load it again when needed.

I also can't see why you have saved and loaded the data at all.

> My program seems to run ok but no output. I suspect I am not reading the data from the file. Using a blank file the results are the same, program runs but no output.
>
> The start of my program loads the file as:
>
> % Part 1
> load file.mat

At this point type 

 who 

To see the variables present. To see how much data is in a variable M type

  size(M)

 

> for i=1:1258
> x(i) = i;
> end

The above can be replaced by

    x = 1:1258;

 

> p1 = polyfit(x', file(1:1258), 3);

I do not know what  the 'file' variable is, but your data should be in M.

 

> xx = (1:1:1358)';
> pp1 = polyval(p1, xx);
> plot(xx, NFLXdata)
> hold
>
> I can run commands and get the samples in documentation to work, but I am missing something with inputting data from file.
>
> Rich

Hope this helps. If not I would encourage you to read the manual and try a few more exanples out.

Ian