How to Use Character String as a For Loop Variable.

I am attempting to use a character string as a variable in the following for loop:

Spring_Type = "Closed and Ground";
  if Spring_Type = "Open";
      Pitch = (Free_Length - D_Wire)/A_Coils;
  elseif Spring_Type = "Open and Ground";
      Pitch = Free_Length/Tot_Coils;
  Pitch = (Free_Length - (2*D_Wire))/A_Coils;
  elseif Spring_Type = "Closed";
      Pitch = (Free_Length - (3*D_Wire))/A_Coils;
  elseif Spring_Type = "Closed and Ground";
      Pitch = (Free_Length - (2*D_Wire))/A_Coils;
  end

All the other variables are fully defined in a section before this. When I run this section I get the following error:

Could someone explain why I cannot use a character string as a variable, and if there is an alternative way to achieve what I am doing?

Many thanks,

Answer 1

[jonas]

The condition must output a logical. Use e.g. isequal or ==

if isequal(Spring_type,'Open')
 ...
end

or

if Spring_type == 'Open'
 ...
end