tfer_tri.m

% TFER_TRI Evaluates the transfer function for a PMA as a triangular function.
% Author: Timothy Sipkens, 2018-12-27
% 
% Inputs:
%   sp          Structure defining various setpoint parameters 
%               (e.g. m_star, V). Use 'get_setpoint' method to generate 
%               this structure.
%   m           Particle mass
%   ~           Placeholder for mobility diameter
%   ~           Placeholder for integer charge state
%   ~           Placeholder for device properties (e.g. classifier length)
%
% Outputs:
%   Lambda      Transfer function
%=========================================================================%

function [Lambda] = tfer_tri(sp,m,~,~,~)

m_del = [sp.m_max]' - [sp.m_star]'; % FWHM of the transfer function (related to resolution)
m_min = 2 .* [sp.m_star]' - [sp.m_max]'; % lower end of the transfer function

% Evaluate the transfer function.
Lambda = zeros(length(sp), length(m))+...
    (m <= [sp.m_star]') .* (m > m_min) .* (m - m_min) ./ m_del + ...
    (m > [sp.m_star]') .* (m < [sp.m_max]') .* (([sp.m_star]' - m) ./ m_del + 1);

end