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5

T[t_] := {(-Sin[t])/(Sqrt[1 + Cos[t/2]^2]), (Cos[t])/(Sqrt[1 + Cos[t/2]^2]), (Cos[t/2])/(Sqrt[1 + Cos[t/2]^2])} B[t_] := Rationalize@{(-0.5 Cos[t] Sin[t/2] + Cos[t/2] Sin[t]) Sqrt[1.625 + 0.375 Cos[t]], (-Cos[t/2] Cos[t] - 0.5 Sin[t/2] Sin[t])/Sqrt[1.625 + 0.375 Cos[t]], 1/Sqrt[1.625 + ...


4

Mathematica 10 provides new functionality dealing with curves, (see e.g. the Vector Analysis tutorial) like ArcLength, ArcCurvature and especially FrenetSerretSystem: FrenetSerretSystem[{ x1, ..., xn}, t] gives the generalized curvatures and Frenet-Serret basis for the parametric curve x[t] i.e. it returns {{ k1, ..., k(n-1)}, { e1, ..., en}}, where ki ...


0

You want CoefficientArrays: CoefficientArrays[V, var] // Last // Normal {{exp1, exp2, exp3}, {exp4, exp5, exp6}, {exp7, exp8, exp9}}


1

Use Coefficient: var = {a, b, c} V = {a*exp1+b*exp2+c*exp3, a*exp4+b*exp5+c*exp6, a*exp7+b*exp8+c*exp9} Transpose[Map[Coefficient[V, #] &, var]] {{exp1, exp2, exp3}, {exp4, exp5, exp6}, {exp7, exp8, exp9}}



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