How to read text line and assign value to variable?

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Many tech files have header like this:
int display_order = 1;
int bigendian = 0;
float imagescale = 1.000000000;
float psi = 359.9580;
float phi = 0.0000;
float theta = 90.0000;
float orientation[] = {-1.0000,0.0007,-0.0000,-0.0000,-0.0000,1.0000,0.0007,1.0000,0.0000};
How can each line be assigned to the variable with value (after fgetl)?
For example: the line float
psi = 359.9580;
psi = float(359.9580);
  1 Comment
dpb on 15 Oct 2018
float is not valid Matlab data type; either single or double; double is default and Matlab also is un-typed for numeric classes; integers are by default stored as double as well.
You could almost turn it into an m-file as is simply by dropping the first word of each line and rewriting; the empty [] in the array are the only thing preventing that in that sample although the curlies "{}" instead of parenetheses would create a cell array instead of a base numeric array.

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Accepted Answer

KSSV on 16 Oct 2018
fid = fopen('data.txt','r') ;
S = textscan(fid,'%s','delimiter','\n') ;
fclose(fid) ;
% GEt the line where psi lies
S = S{1} ;
idx = contains(S,'psi') ;
S = S(idx) ;
S = strsplit(S{1}) ;
psi = str2num(S{4})
Stephen23 on 16 Oct 2018
Edited: Stephen23 on 16 Oct 2018
@John: In general it is a bad idea to magically access a variable name. Read this to know why:
You could write a function and use inputname.

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