// function sys = lti_vol_1(vol, beta, spgr)
// Building block for a volume having two flow inputs.
// Author:   D. A. Gutz
// Written:  16-Apr-92
// Revisions:None.
// 
// Input:
// beta  Fluid bulk modulus, psi.
// spgr  Fluid specific gravity.
// vol   Volume, cuin.
// wfs   Input # 1, supply flow, pph.
// wfd   Input # 2, discharge flow, pph.
// 
// Output:
// sys   Packed system of Input and Output
// 
// Differential I/O:
// wfs   Input # 1, supply flow, pph
// wfd   Input # 2, discharge flow, pph
// p     Output # 1, slice pressure, psid.
// Copyright (C) 2018 - Dave Gutz
//
// Permission is hereby granted, free of charge, to any person obtaining a copy
// of this software and associated documentation files (the "Software"), to deal
// in the Software without restriction, including without limitation the rights
// to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
// copies of the Software, and to permit persons to whom the Software is
// furnished to do so, subject to the following conditions:
//
// The above copyright notice and this permission notice shall be included in all
// copies or substantial portions of the Software.
//
// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
// IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
// FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
// AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
// LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
// OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
// SOFTWARE.
// Oct 10, 2018 	DA Gutz		Created
// ******************************************************************************
function [sys] = lti_vol_1(vol,%beta,spgr)

    // Output variables initialisation (not found in input variables)
    sys=[];

    // Display mode
    mode(0);

    // Display warning for floating point exception
    ieee(1);

    // Derivative
    dp = ((%beta/129.93948)/vol)/spgr;// Derivative, psi/sec.
    a = 0;
    b = [dp,-dp];
    c = 1;
    e = [0,0];

    // Form the system.
    sys = pack_ss(a,b,c,e);

endfunction
