StandardLinearOscillatorVelocityFilter.cppGo to the documentation of this file.00001 /* ****************************************************************** ** 00002 ** OpenSees - Open System for Earthquake Engineering Simulation ** 00003 ** Pacific Earthquake Engineering Research Center ** 00004 ** ** 00005 ** ** 00006 ** (C) Copyright 2001, The Regents of the University of California ** 00007 ** All Rights Reserved. ** 00008 ** ** 00009 ** Commercial use of this program without express permission of the ** 00010 ** University of California, Berkeley, is strictly prohibited. See ** 00011 ** file 'COPYRIGHT' in main directory for information on usage and ** 00012 ** redistribution, and for a DISCLAIMER OF ALL WARRANTIES. ** 00013 ** ** 00014 ** Developed by: ** 00015 ** Frank McKenna (fmckenna@ce.berkeley.edu) ** 00016 ** Gregory L. Fenves (fenves@ce.berkeley.edu) ** 00017 ** Filip C. Filippou (filippou@ce.berkeley.edu) ** 00018 ** ** 00019 ** Reliability module developed by: ** 00020 ** Terje Haukaas (haukaas@ce.berkeley.edu) ** 00021 ** Armen Der Kiureghian (adk@ce.berkeley.edu) ** 00022 ** ** 00023 ** ****************************************************************** */ 00024 00025 // $Revision: 1.3 $ 00026 // $Date: 2003/10/27 23:04:40 $ 00027 // $Source: /usr/local/cvs/OpenSees/SRC/reliability/domain/filter/StandardLinearOscillatorVelocityFilter.cpp,v $ 00028 00029 00030 // 00031 // Written by Terje Haukaas (haukaas@ce.berkeley.edu) 00032 // 00033 00034 #include <StandardLinearOscillatorVelocityFilter.h> 00035 #include <Filter.h> 00036 #include <classTags.h> 00037 00038 00039 StandardLinearOscillatorVelocityFilter::StandardLinearOscillatorVelocityFilter(int tag, double period, double dampingRatio) 00040 :Filter(tag,FILTER_standardLinearOscillator) 00041 { 00042 double pi = 3.14159265358979; 00043 wn = 2*pi/period; 00044 xi = dampingRatio; 00045 } 00046 00047 StandardLinearOscillatorVelocityFilter::~StandardLinearOscillatorVelocityFilter() 00048 { 00049 } 00050 00051 double 00052 StandardLinearOscillatorVelocityFilter::getAmplitude(double time) 00053 { 00054 if (time<0.0) { 00055 return 0.0; 00056 } 00057 else { 00058 double wd = wn * sqrt(1.0-pow(xi,2.0)); 00059 return ( ( wd*cos(wd*time) - xi*wn*sin(wd*time) ) * exp(-xi*wn*time) ); 00060 // Should maybe include the 1/mwd factor too 00061 } 00062 } 00063 00064 double 00065 StandardLinearOscillatorVelocityFilter::getMaxAmplitude() 00066 { 00067 double wd = wn * sqrt(1.0-pow(xi,2.0)); 00068 00069 opserr << "ERROR: The getMaxAmplitude() method is not implemented for velocity filter." << endln; 00070 00071 double result = 0.0; 00072 00073 return result; 00074 } 00075 00076 double 00077 StandardLinearOscillatorVelocityFilter::getTimeOfMaxAmplitude() 00078 { 00079 double wd = wn * sqrt(1.0-pow(xi,2.0)); 00080 00081 opserr << "ERROR: The getTimeOfMaxAmplitude() method is not implemented for velocity filter." << endln; 00082 00083 return 0.0; 00084 } 00085 00086 void 00087 StandardLinearOscillatorVelocityFilter::Print(OPS_Stream &s, int flag) 00088 { 00089 } |