Hi everyone! Just a quick question

When I use the Discrete Plot command. For example

DiscretePlot([1,2,3,4,5],[1,6,2,3,4],style=stem)

I get a graph looking like this 

Now, if possible, I would like to be able to have an indent between 0 and 1 to make it look a bit nicer.

I'm quite new to Maple but need it for work. I'm trying to work with metric tensors, and for easy examples it does work. For instance, such as here: https://gyazo.com/730e055f3393956ffe41427e11fa1b43

For more complicated problems I come into problems of recognising my tensors as actual metrics. In particular here: https://gyazo.com/58347c676b98ddf99275eea8cfecc69d

What am I doing wrong here? Is there some trick I'm missing, am I giving the data incorrectly?

Thank you,

Eivind

PS: For convenience I'm dumping the document in text format here:

> restart;
> with(PDETools); with(DifferentialGeometry); with(Tools); with(Tensor);
> k := 4;
                               4
> C := [w1, w2, z1, z2, seq(cat(x, i), i = 1 .. k), seq(cat(y, i), i = 1 .. k)];
        [w1, w2, z1, z2, x1, x2, x3, x4, y1, y2, y3, y4]
> DGsetup(C, PW, quiet);
                         frame name: PW
PW > F := [b, seq(cat(r, i), i = 1 .. k), seq(cat(s, i), i = 1 .. k)];
              [b, r1, r2, r3, r4, s1, s2, s3, s4]
PW > FunGen := proc (symb) options operator, arrow; PDETools[declare](symb(w1, w2), symb) end proc;
PW > map(FunGen, F);
              b(w1, w2) will now be displayed as b
             r1(w1, w2) will now be displayed as r1
             r2(w1, w2) will now be displayed as r2
             r3(w1, w2) will now be displayed as r3
             r4(w1, w2) will now be displayed as r4
             s1(w1, w2) will now be displayed as s1
             s2(w1, w2) will now be displayed as s2
             s3(w1, w2) will now be displayed as s3
             s4(w1, w2) will now be displayed as s4
PW > NULL;
PW > dx := proc (i) options operator, arrow; 'eval(cat(dx, i))' end proc;
PW > dy := proc (i) options operator, arrow; 'eval(cat(dy, i))' end proc;
PW > r := proc (i) options operator, arrow; cat(r, i) end proc;
PW > s := proc (i) options operator, arrow; cat(s, i) end proc;
PW > epsilon := proc (i) options operator, arrow; cat(epsilon, i) end proc;
PW > L1 := [1, b, seq(r(i), i = 1 .. k), seq(s(i), i = 1 .. k), seq(epsilon(i), i = 1 .. k)];
  [1, b, r1, r2, r3, r4, s1, s2, s3, s4, epsilon1, epsilon2,

    epsilon3, epsilon4]
PW > g := evalDG(`&s`(dw1, dz2)+`&s`(dw2, dz2)+b*(`&s`(dw1, dw1)+`&s`(dw2, dw2))+sum('r(i)'*(`&s`(dx(i), dw1)+`&s`(dy(i), dw2)), i = 1 .. k)+sum('s(i)'*(`&s`(dx(i), dw2)-`&s`(dx(i), dw1)), i = 1 .. k)+sum('epsilon(i)'*(`&s`(dx(i), dx(i))+`&s`(dy(i), dy(i))), i = 1 .. k));
_DG([["tensor", PW, [["cov_bas", "cov_bas"], []]], [

  [[1, 1], 2 b], [[1, 4], 1], [[1, 5], -s1 + r1],

  [[1, 6], -s2 + r2], [[1, 7], -s3 + r3], [[1, 8], -s4 + r4],

  [[2, 2], 2 b], [[2, 4], 1], [[2, 5], s1], [[2, 6], s2],

  [[2, 7], s3], [[2, 8], s4], [[2, 9], r1], [[2, 10], r2],

  [[2, 11], r3], [[2, 12], r4], [[4, 1], 1], [[4, 2], 1],

  [[5, 1], -s1 + r1], [[5, 2], s1], [[5, 5], 2 epsilon1],

  [[6, 1], -s2 + r2], [[6, 2], s2], [[6, 6], 2 epsilon2],

  [[7, 1], -s3 + r3], [[7, 2], s3], [[7, 7], 2 epsilon3],

  [[8, 1], -s4 + r4], [[8, 2], s4], [[8, 8], 2 epsilon4],

  [[9, 2], r1], [[9, 9], 2 epsilon1], [[10, 2], r2],

  [[10, 10], 2 epsilon2], [[11, 2], r3], [[11, 11], 2 epsilon3],

  [[12, 2], r4], [[12, 12], 2 epsilon4]]])
PW > Gam := Christoffel(g);
Error, (in DifferentialGeometry:-Tensor:-Christoffel) expected 1st argument to be a metric tensor. Received: _DG([["tensor", PW, [["cov_bas", "cov_bas"], []]], [`...`]])
PW > Ric := RicciScalar(g);
Error, (in DifferentialGeometry:-Tensor:-RicciScalar) expected 1st argument to be metric tensor. Received: _DG([["tensor", PW, [["cov_bas", "cov_bas"], []]], [`...`]])
PW > CovariantDerivative(g, Gam);
Error, (in DifferentialGeometry:-Tensor:-CovariantDerivative) expected 2nd argument to be an affine connection. Received: Gam
PW > LieDerivative(D_x, g);
Error, (in DifferentialGeometry:-LieDerivative) expected 1st argument to be a vector field. Received D_x
PW > CurvatureTensor(g);
Error, (in DifferentialGeometry:-Tensor:-CurvatureTensor) expected 1st argument to be a metric tensor or an  affine connection. Received: _DG([["tensor", PW, [["cov_bas", "cov_bas"], []]], [`...`]])
PW >

Hi everyone again

This one is linked to my previous 2 question.

Essentially I am trying to use a procedure to reproduce the formula:

S(j) = (1 + sum(H_j*T_j,j=1..n))/(1 + sum(1/(H_j*T_j),j=1..n))

BigProc:= proc(H::list,T::list)
local Form, i;
Form:=[];
for i from 1 to nops(H) do
Form := [op(Form),(1 + [sum(H[1..i]*~T[1..i],i=1..5)])/~(1 + [sum(1/~(H[1..i]*~T[1..i]),i=1..5)])]
end do:
end proc:
MainProc([1,3,5],[3,6,8])

Error, (in sum) summation variable previously assigned, second argument evaluates to 1 = 1 .. 5
 

The actual answer should be (3, 396/25,22320/509)

ie 

S(1) = (1+ 3)/(1+(1/3)) = 3

S(2) = (1 +(3+18))/(1+1/3 + 1/18)) = 396/25

S(3) = (1 +(3+18+40))/(1+1/3 + 1/18 +1/40) = 22320/509

I feel like I am missing a few things to my procedure. Any help would be greatly appreciated!

The output of a solve command was:

solution := {p[1] = 2.788944999, p[2] = 4.940143518}, { p[1] = 15.29764736, p[2] = 4.946617373}

My question is: How to capture these 4 numbers in a 2 by 2 matrix ?

I tried assign, subs commands. Did not succeed. Could some one help, please?

Hi

I would like to be able to use a procedure in order to create a sequence using a list. Here is an example of what I am trying to achieve:

X = [1,3,4, 50,10]

T_n = 1 + sum^n_j=1 X_j

So T_1 = 1 + 1 = 2

T_2 = 1 + [1+3] = 5

T_3 = 1 +[1+3 +4] = 9

T_4 = 1 + [1+3+4+50] = 59

T_5 = 1+ [1+3+4+50+10] = 69

So my final list would be [2,5,9,59,69]

I am quite new to this forum so i was not sure how to create the Sum from j = 1 to n bit. I know the command for creating a summation but not in a procedure sense.

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I have the following expression,

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