Circuit Estimation
/*--------------------------------------------------------------
SAS Sample Library
Name: modex09.sas
Description: Example program from SAS/ETS User's Guide,
The MODEL Procedure
Title: Circuit Estimation
Product: SAS/ETS Software
Keys: nonlinear simultaneous equation models
PROC: MODEL
Notes:
--------------------------------------------------------------*/
data circ;
input v2 v1 time@@;
datalines;
-0.00007 0.0 0.0000000001 0.00912 0.5 0.0000000002
0.03091 1.0 0.0000000003 0.06419 1.5 0.0000000004
0.11019 2.0 0.0000000005 0.16398 2.5 0.0000000006
0.23048 3.0 0.0000000007 0.30529 3.5 0.0000000008
0.39394 4.0 0.0000000009 0.49121 4.5 0.0000000010
0.59476 5.0 0.0000000011 0.70285 5.0 0.0000000012
0.81315 5.0 0.0000000013 0.90929 5.0 0.0000000014
1.01412 5.0 0.0000000015 1.11386 5.0 0.0000000016
1.21106 5.0 0.0000000017 1.30237 5.0 0.0000000018
1.40461 5.0 0.0000000019 1.48624 5.0 0.0000000020
1.57894 5.0 0.0000000021 1.66471 5.0 0.0000000022
;
title1 'Circuit Model Estimation Example';
proc model data=circ mintimestep=1.0e-23;
parm R2 2000 R1 4000 C 5.0e-13;
dert.v2 = (v1-v2)/((r1 + r2*(1-exp( -(v1-v2)))) * C);
fit v2;
run;