function output = igm_specific_heats(name, temperature, units)
% -------------------------------------------------------------------------
% igm_specific_heats
% -------------------------------------------------------------------------
% Fundamentals of Thermodynamics
% A function that uses the ideal gas model (IGM) and temperature of gases 
% (Air, Nitrogen, Oxygen, Carbon Dioxide, Carbon Monoxide, Hydrogen) to 
% define as the output a structure with relevant specific heat and 
% other properties at the same state. 
% -------------------------------------------------------------------------
% Syntax: output = igm_specific_heats(name, temperature, units)
% Inputs: name = name of common gases ('Air', 'Nitrogen', 'Oxygen', 
%         'Carbon Dioxide', 'Carbon Monoxide' or 'Hydrogen') 
%         temperature = the value of the temperature (K or F)
%         units = 1 (SI units) or 2 (English units)
% Output: output = the structure with relevant specific heat and other 
%         properties in corresponding fields (T, cp, cv, k, M, R)
%         
% Valid properties and units:
%         T - temperature (K or F)
%         cp - specific heat at constant pressure (kJ/kg*K or Btu/lb*R)
%         cv - specific heat at constant volume (kJ/kg*K or Btu/lb*R)
%         k - specific heat ratio (unitless)
%         M - molecular weight (kg/kmol or lb/lbmol)
%         R - gas constant (TBD)
%
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% Notes: Use consistent SI or English units. 
% This function is set up for only the gases mentioned above. 
% All specific properties defined per unit mass. 
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% Example
% output = igm_specific_heats('Air', 300, 1)
% This example corresponds to air at 300 degrees K.
%--------------------------------------------------------------------------
% Dr.Priya Goeser, Professor
% Robyn Callaghan, Undergraduate student, Mechanical Engineering
% Original: June 6, 2016
% Modified: July 20, 2016
% Copyright (c) 2016 Robyn Callaghan, All Rights Reserved.
% Engineering Studies Program, Armstrong State University.
% -------------------------------------------------------------------------