MATLAB function trouble using (wtls_line)

[NeoGenus59]

Hello,

I'm new here and I'm trying to figure out how to use MATLAB to crunch some numbers about neutron counts. I have data from a detctor and ultimately I'd like to linearize it!

I'm using wtls_line found at: http://www.mathworks.com/matlabcentral/fileexchange/17466-weighted-total-least-squares-straight-line-fit/content/wtls_line.m

OK so when I go to extract the data--attached, I use a column, from a file of type .m, which is a double (and I believe is the cause of the problem).

Upon trying to use wtls_line, I define xin, yin, uxin, yxin, and guck, (all are necessary to work properly, correct?) Then I type:

[a,b,alpha,p,chiopt,Cab,Calphap]= wtls_line(xin,yin,uxin,uyin,guck)

which returns

Undefined function 'wtls_line' for input arguments of type 'double'.

It may be that I don't know how to properly call upon a function but I think I either need to change the data I'm extracting from double to something else or the problem is something that I don't know. Does anyone have any clue how to solve this issue?

Also, I plan on plotting this information against the same data type (neutron counts) but for other detectors... (may be irrelevant)

I appreciate any help you can offer! Thank you.

-Michael

Figured it out: the file name didn't match the function name. I did a 'save as...' and changed the name. Sorry.

 

[mmwave]

Hi Michael,

Welcome to the forum! It sounds like you are on the right track with using the wtls_line function for your neutron count data analysis. The error message you are receiving is likely due to the function not being properly added to your MATLAB path. To do this, you can either add the folder containing the wtls_line function to your path using the "addpath" command, or you can use the full file path when calling the function (e.g. [a,b,alpha,p,chiopt,Cab,Calphap]= wtls_line('C:\Users\username\Documents\wtls_line.m', xin, yin, uxin, uyin, guck)).

As for the data types, it is important to make sure that your input data (xin, yin, uxin, uyin, guck) are all in the correct format for the function. For example, xin and yin should be vectors of the same length, and uxin and uyin should be the corresponding uncertainties for each data point. It is also important to note that the function assumes the data follows a linear relationship, so if your data does not fit this assumption, the results may not be accurate.

I also wanted to mention that there are other built-in functions in MATLAB that can perform linear regression, such as "polyfit" and "regress". These may be worth looking into as well.

Best of luck with your analysis and let us know if you have any further questions.