## Copyright (C) 2018 Jens Ahrensfeld
## 
## This program is free software; you can redistribute it and/or modify it
## under the terms of the GNU General Public License as published by
## the Free Software Foundation; either version 3 of the License, or
## (at your option) any later version.
## 
## This program is distributed in the hope that it will be useful,
## but WITHOUT ANY WARRANTY; without even the implied warranty of
## MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
## GNU General Public License for more details.
## 
## You should have received a copy of the GNU General Public License
## along with this program.  If not, see <http://www.gnu.org/licenses/>.

## -*- texinfo -*- 
## @deftypefn {Function File} {@var{retval} =} vanDusen_eval (@var{input1}, @var{input2})
##
## @seealso{}
## @end deftypefn

## Author: Jens Ahrensfeld <ahrensfeld@w2ess001vm>
## Created: 2018-05-28

function vanDusen_eval (R0, Tmin, Tmax, dT)

a = +3.90830e-03
b = -5.77500e-07
c = -4.18301e-12

T = Tmin:dT:Tmax;

R1 = R0*(1 + a*T + b*T.^2);
R2 = c.*(T - 100).*T.^3;


a_IEC = 0.00385055;
a_SAMA = 0.00392;

plot(T, R1, T, R0*(1+a_IEC*T), 'r', T, R0*(1+a_SAMA*T), 'g'); grid; xlabel('T/°C'); ylabel('RTD/ohms'); legend('van Dusen','a_{IEC}','a_{SAMA}');


endfunction