{ diff(x1, t) = (1*k25*piecewise(41/1000, k24 = 0, 33/1000) + 1*k25*piecewise(11/200000, k24 = 0, 11/100000)*(x1 + x2 + x3 + x4) + 1*k25*piecewise(27/10000, k24 = 0, 11/20000)*x4 + (-1)*k25*piecewise(33/100, k24 = 0, 1/2)*(x5 + x6 + x7)*piecewise(43/10, k24 = 0, 19)/(piecewise(33/100, k24 = 0, 1/2)*(x5 + x6 + x7) + piecewise(43/10, k24 = 0, 19)*(x1 + x2 + x3 + x4))*piecewise(11/500, k24 = 0, 11/500)*x7/(x5 + x6 + x7)*x1 + (-1)*k25*(piecewise(11/1250000, k24 = 0, 1/62500) + piecewise(1/5000000, k24 = 0, 3/10000000)*(x1 + x2 + x3 + x4))*x1)/k25,
  diff(x2, t) = (1*k25*piecewise(33/100, k24 = 0, 1/2)*(x5 + x6 + x7)*piecewise(43/10, k24 = 0, 19)/(piecewise(33/100, k24 = 0, 1/2)*(x5 + x6 + x7) + piecewise(43/10, k24 = 0, 19)*(x1 + x2 + x3 + x4))*piecewise(11/500, k24 = 0, 11/500)*x7/(x5 + x6 + x7)*x1 + (-1)*k25*piecewise(1/10, k24 = 0, 1/10)*x2 + (-1)*k25*(piecewise(11/1250000, k24 = 0, 1/62500) + piecewise(1/5000000, k24 = 0, 3/10000000)*(x1 + x2 + x3 + x4))*x2)/k25,
  diff(x3, t) = (1*k25*piecewise(1/10, k24 = 0, 1/10)*x2 + (-1)*k25*piecewise(7/2000, k24 = 0, 7/2000)*x3 + (-1)*k25*piecewise(9/500000, k24 = 0, 9/100000)*x3 + (-1)*k25*(piecewise(11/1250000, k24 = 0, 1/62500) + piecewise(1/5000000, k24 = 0, 3/10000000)*(x1 + x2 + x3 + x4))*x3)/k25,
  diff(x4, t) = ((-1)*k25*piecewise(27/10000, k24 = 0, 11/20000)*x4 + 1*k25*piecewise(7/2000, k24 = 0, 7/2000)*x3 + (-1)*k25*(piecewise(11/1250000, k24 = 0, 1/62500) + piecewise(1/5000000, k24 = 0, 3/10000000)*(x1 + x2 + x3 + x4))*x4)/k25,
  diff(x5, t) = (1*k26*piecewise(13/100, k24 = 0, 13/100)*(x5 + x6 + x7) + (-1)*k26*piecewise(33/100, k24 = 0, 1/2)*piecewise(43/10, k24 = 0, 19)*(x1 + x2 + x3 + x4)/(piecewise(33/100, k24 = 0, 1/2)*(x5 + x6 + x7) + piecewise(43/10, k24 = 0, 19)*(x1 + x2 + x3 + x4))*(piecewise(6/25, k24 = 0, 12/25)*x3/(x1 + x2 + x3 + x4) + piecewise(3/125, k24 = 0, 6/125)*x4/(x1 + x2 + x3 + x4))*x5 + (-1)*k26*(piecewise(33/1000, k24 = 0, 33/1000) + piecewise(1/25000, k24 = 0, 1/50000)*(x5 + x6 + x7))*x5)/k26,
  diff(x6, t) = (1*k26*piecewise(33/100, k24 = 0, 1/2)*piecewise(43/10, k24 = 0, 19)*(x1 + x2 + x3 + x4)/(piecewise(33/100, k24 = 0, 1/2)*(x5 + x6 + x7) + piecewise(43/10, k24 = 0, 19)*(x1 + x2 + x3 + x4))*(piecewise(6/25, k24 = 0, 12/25)*x3/(x1 + x2 + x3 + x4) + piecewise(3/125, k24 = 0, 6/125)*x4/(x1 + x2 + x3 + x4))*x5 + (-1)*k26*piecewise(83/1000, k24 = 0, 91/1000)*x6 + (-1)*k26*(piecewise(33/1000, k24 = 0, 33/1000) + piecewise(1/25000, k24 = 0, 1/50000)*(x5 + x6 + x7))*x6)/k26,
  diff(x7, t) = (1*k26*piecewise(83/1000, k24 = 0, 91/1000)*x6 + (-1)*k26*(piecewise(33/1000, k24 = 0, 33/1000) + piecewise(1/25000, k24 = 0, 1/50000)*(x5 + x6 + x7))*x7)/k26 }