# Protected Tag list and not a vector errors [duplicate]

I am working on a project for school, and I just need to find when the angle between a tangent vector and a line formed between two points. Here is the code I'm using:

v[t_] = Simplify[{{0.95, 0.4, 0.35} - rsSpline[t]}];


rsSpline is vector path that is defined earlier, I'll include it at the bottom. When I run this code I get a Tag list in __ is protected. Any ideas on how to get the angle[t] to be evaluated?

rsSpline[t_] = {Piecewise[{{0.,
t > 20 || t < 0}, {-0.2937381672928643 +
0.15040714998600957*t - 0.009814309237081695*t^2 +
0.0002765249899592576*t^3,
Inequality[40/3, LessEqual, t, LessEqual,
20]}, {0.15859527846615362 + 0.048632124690230844*t -
0.0021811823398982626*t^2 + 0.00008569681752967245*t^3,
Inequality[20/3, LessEqual, t, Less, 40/3]}},
0.007407407407407408 + 0.11666666666666667*t -
0.012386363636363633*t^2 + 0.0005959558823529409*t^3],
Piecewise[{{0.,
t > 20 || t < 0}, {2.3628688879724002 - 0.40432249899261*t +
0.03270443866666542*t^2 - 0.0009146400119319888*t^3,
Inequality[40/3, LessEqual, t, LessEqual,
20]}, {0.5328657794849881 - 0.022883925511597986*t +
0.00864336454488792*t^2 - 0.0005404541033524712*t^3,
Inequality[0, LessEqual, t, LessEqual, 20/3]}},
0.39814521980207296 + 0.03774032634571389*t -
0.0004502732337088676*t^2 - 0.00008577221442263185*t^3],
Piecewise[{{0.,
t > 20 || t < 0}, {-0.13132189257653604 +
0.1485145520804218*t - 0.013373484217090448*t^2 +
0.00036857764236616127*t^3,
Inequality[40/3, LessEqual, t, LessEqual, 20]}, {0.7 -
0.03263184092261795*t - 0.0006726596658646056*t^2 +
0.00009531477478562237*t^3,
Inequality[0, LessEqual, t, LessEqual, 20/3]}},
0.7262268125630266 - 0.04443390657597979*t +
0.00109765018213967*t^2 + 6.799282385408284*^-6*t^3]};

• v[t_] := Simplify[{0.95, 0.4, 0.35} - rsSpline[t]]; angle[t_] := VectorAngle[rsSpline'[t], v[t]]. Note: (i) you should you SetDelayed (ii) the extra curly brackets in v[t] definition lead to the error->remove. – ubpdqn Feb 14 '15 at 1:34
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• @ubpdqn Thank you, I've fixed those but I still don't have the Tags protected fixed. I'd upvote but I don't have the reputation. – Hovestar Feb 14 '15 at 1:44
• @Hovestar I have run the corrected code on a fresh session with no errors, e.g. Table[angle[j], {j, 0.1, 1, 0.1}] yielded {0.0887941, 0.0788714, 0.0691422, 0.0599565, 0.0519149, 0.0459925, \ 0.043476, 0.0453416, 0.0514755, 0.0609099}. So, I suggest saving, quitting kernel and starting fresh session. – ubpdqn Feb 14 '15 at 1:48
• @ubpdqn That worked! Could you put that as an answer so I can mark this as completed? – Hovestar Feb 14 '15 at 1:51

v[t_] := Simplify[{0.95, 0.4, 0.35} - rsSpline[t]];


Note: (i) you should you SetDelayed (ii) the extra curly brackets in v[t] definition lead to the error->remove

I have run the corrected code on a fresh session with no errors, e.g.

Table[angle[j], {j, 0.1, 1, 0.1}]


yielded

{0.0887941, 0.0788714, 0.0691422, 0.0599565, 0.0519149, 0.0459925, 0.043476, 0.0453416,
0.0514755, 0.0609099}


So, I suggest saving, quitting kernel and starting fresh session.