Test the variable type from file input

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katerina
katerina on 21 Aug 2014
Edited: per isakson on 22 Aug 2014
I recall a way in Verilog to test a char read in from a file (like a buffer, I believe) and then based on what that char is, proceed in a certain way.
My current file reading uses fscanf and reads in only numbers, but the users here sometimes user True/False for a line, and sometimes 0/1. An example of a line could be either:
Fruit Bananas True Potatoes False
~~ or ~~
Fruit Bananas 1 Potatoes 0
I'm trying to migrate toward 0/1, since I don't think Matlab recognizes True/False like python can. So I want to be able to read in either file type. If the scan returns a number (after the fruit type), then I proceed with numbers, if it returns a char or string, then I proceed for that. Does anyone have suggestions? Thanks!
&nbsp
EDIT: My actual input file looks more like this: (a mixture)
VAR1 55.6
VAR2 23
VAR3 0
VAR4
VAR5
VAR6 -999
VAR7 True
VAR8 False
VAR9 0
VAR10 1

Accepted Answer

per isakson
per isakson on 21 Aug 2014
Edited: per isakson on 21 Aug 2014
Another approach
fid = fopen('bananas.txt','r');
cac = textscan( fid, '%s%s%s%s%s' );
fclose( fid )
isb = cellfun( @(str) logical( eval( lower( str ) ) ), cac{3} );
where bananas.txt contains the two lines
Fruit Bananas True Potatoes False
Fruit Bananas 1 Potatoes 0
Inspect isb
>> whos isb
Name Size Bytes Class Attributes
isb 2x1 2 logical
  5 Comments
per isakson
per isakson on 22 Aug 2014
  • "I'm trying to migrate toward 0/1" &nbsp Why not stick with True/False? That makes the file more readable in the editor. What if '1' means numerical 1 for some other variable, e.g. VAR1
  • "I don't think Matlab recognizes True/False like python" &nbsp I don't know Python well enough to understand the meaning of this statement.

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More Answers (1)

the cyclist
the cyclist on 21 Aug 2014
Edited: the cyclist on 21 Aug 2014
There are ischar() and isnumeric() functions in MATLAB, to identify particular variable types, as well as the class() function.
Also, MATLAB will recognize true and false as logical values.
  2 Comments
katerina
katerina on 21 Aug 2014
I realize I could just read in the string and convert it if needed, but I'd like a clean way to discriminate between reading a number or "True"/"False".

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