GEN_BUS     = 1;    // bus number
PG          = 2;    // Pg, real power output (MW)
QG          = 3;    // Qg, reactive power output (MVAr)
QMAX        = 4;    // Qmax, maximum reactive power output at Pmin (MVAr)
QMIN        = 5;    // Qmin, minimum reactive power output at Pmin (MVAr)
VG          = 6;    // Vg, voltage magnitude setpoint (p.u.)
MBASE       = 7;    // mBase, total MVA base of this machine, defaults to baseMVA
GEN_STATUS  = 8;    // status, 1 - machine in service, 0 - machine out of service
PMAX        = 9;    // Pmax, maximum real power output (MW)
PMIN        = 10;   // Pmin, minimum real power output (MW)
PC1         = 11;   // Pc1, lower real power output of PQ capability curve (MW)
PC2         = 12;   // Pc2, upper real power output of PQ capability curve (MW)
QC1MIN      = 13;   // Qc1min, minimum reactive power output at Pc1 (MVAr)
QC1MAX      = 14;   // Qc1max, maximum reactive power output at Pc1 (MVAr)
QC2MIN      = 15;   // Qc2min, minimum reactive power output at Pc2 (MVAr)
QC2MAX      = 16;   // Qc2max, maximum reactive power output at Pc2 (MVAr)
RAMP_AGC    = 17;   // ramp rate for load following/AGC (MW/min)
RAMP_10     = 18;   // ramp rate for 10 minute reserves (MW)
RAMP_30     = 19;   // ramp rate for 30 minute reserves (MW)
RAMP_Q      = 20;   // ramp rate for reactive power (2 sec timescale) (MVAr/min)
APF         = 21;   // area participation factor

// included in opf solution, not necessarily in input
// assume objective function has units, u
MU_PMAX     = 22;   // Kuhn-Tucker multiplier on upper Pg limit (u/MW)
MU_PMIN     = 23;   // Kuhn-Tucker multiplier on lower Pg limit (u/MW)
MU_QMAX     = 24;   // Kuhn-Tucker multiplier on upper Qg limit (u/MVAr)
MU_QMIN     = 25;   // Kuhn-Tucker multiplier on lower Qg limit (u/MVAr)

// Note: When a generator's PQ capability curve is not simply a box and the
// upper Qg limit is binding, the multiplier on this constraint is split into
// it's P and Q components and combined with the appropriate MU_Pxxx and
// MU_Qxxx values. Likewise for the lower Q limits.