Strange file output while using fprintf

Hi Everyone, thank you in advance for your help. I'm trying to write two columns in a txt file using fprintf.

fprintf(filesave2,'%d %\r\n', X, Y);

I even tried manipulating the numbers of characters i wanted to print:

fprintf(filesave2,'%3d %7.5f\r\n', X, Y);

but all in vain. It keeps giving me very strange results.

Results:

9 9.00000

9 9.00000

9 9.00000
..... and so on.

My original data

looks like this:

X is a vector from 5 to 300 with intervals of 5. i.e. 5 10 15 ... 300

Y is a vector with power values 0.46957 0.41538 0.37951 .. etc (60 values).

How can i fix this? So that the written file looks like:

5 0.46957

10 0.41538

15 0.37951

...
etc

Thank you so much for your help!

Answer 1

[Walter Roberson]

fprintf(filesave2,'%d %f\r\n', [X(:), Y(:)].' );

[Hissam Aziz]

hi thank you so much for the help, i'm getting an error "CAT arguments dimensions are not consistent." maybe because i'm trying to store them from matrices. Will try to fix it, what i wanted to know was what does the last part ".'" in your code do?

[Walter Roberson]

Please re-check that X and Y have exactly the same number of elements. Whether they are row vectors or column vectors or matrices does not matter for the code I gave, as long as the number of them is the same.

The .' is matrix transpose. The first part, [X(:), Y(:)] is forming an array of two columns, X and Y, and the .' flips that around so that X becomes the first row and Y becomes the second row. You need to do this for your fprintf() because fprintf() follows values down the columns -- so you want the first column to have an X value and then a Y value (to print them side by side), and the next column to have the second X and Y values, and so on.

If you knew for sure that X and Y are row vectors, then you could instead have coded as

fprintf(filesave2,'%d %f\r\n', [X;Y] );

[Hissam Aziz]

Ahh fixed it! Worked like a charm!