Help with cell if statement

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Charles verhoog
Charles verhoog on 25 Jan 2016
Edited: Guillaume on 25 Jan 2016
Trying to make this code work
if Gas_driven(n) == {'Air'}
R = 286.9;
elseif Gas_driven(n) == 'Argon'
R = 208;
'Gas Constant not defined'
but it keeps coming up with this error
Undefined function or variable 'Air'.
Error in ExpansionShots (line 40)
if Gas_driven(n) == {Air}
  1 Comment
Stephen23 on 25 Jan 2016
Edited: Stephen23 on 25 Jan 2016
The error message indicates that you are actually calling this ( Air is a variable/function):
if Gas_driven(n) == {Air}
but your code shows that you think that you are calling this ( 'Air' is a string):
if Gas_driven(n) == {'Air'}
Also note that == does not check if two strings are the same: you need to use strcmp or strcmpi, exactly as per Ilham Hardy's answer.

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Answers (1)

Ilham Hardy
Ilham Hardy on 25 Jan 2016
Perhaps something like this?
if strcmpi(Gas_driven{n},'Air') == 1
R = 286.9;
elseif strcmpi(Gas_driven{n},'Argon') == 1
R = 208;
R = 'Gas Constant not defined';


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