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Hi,

I'm writting because I don't know how to solve this problem. I look for it in the web, but I don't

find the solution.

I have a vector with 4 variables, for example:

[54*a +3*b -c +d, 32*a -c +d, 96*b -69*c +85*d, 6*a + 9*b+3*c+9*d]

In really there is 4 equations. And I need to solve with other vector like:

[0,0,0,0]

I don't know the commands for do this... I search it in internet but I don't find anything.

How can a vector A=<2,3> be summed to 5.

I've created a matrix in which each row has two values. I'm using Add(i,i=[matrixName][row element number])/2 to find the mean of each row, which I'd like to transfer to a corresponding element number in an array or a vector, but so far I can only get it to work on single rows or (if I use only Add(i,i=[matrixName]/2), understandably, the mean of the whole matrix. Is there a way to do it wholesale?

In Vector Calculus there are excellent commands for finding the normal vector to a curve (PrincipalNormal and TNBFrame) but none for finding the surface normal vector. It is possible to display the surface normal vector using PlotPositionVector's normal option, but this is good for visualization only, and the vector can't be used for further calculations.

Am I missing something, or is this really missing form the package?

Two example problems to be solved:

Hi everybody,

I have a matrix A=[a[ij]]    MXM,

two vectors    X=[x[i]]    Mx1       and    Y=[y[i]]      Mx1  

I want to plot the following

1) 

                             a[11] with x[1] and y[1]

                             a[21...

I need this quite often, but never found a nice way of getting the index of minimal or maximal value of a Vector (or a list or whatever). Is there an easier way than the following?

N := 15:
L := LinearAlgebra[RandomVector](N):
m := min(L):
for i to N do if L[i] = m then print(i); break end if end do;

Given a vector with six elements called, say, c, how do I assign the sum of its values to a name called d without having to write d=c[1]+c[2]...?

Thanks in advance.

Hi. I have a question that concerns indices of vector of functions within for-loop.

I have a following piece of code:

First of, thank you commenters, you have helped me so much in the past!

I am doing a matrix inversion with random numbers and I would like to loop the process, and have each inverstion go into a matrix, such that the matrix will be a bunch of rows ( i number of rows) and three columns (the matrix inversion yeieds three values)

> for i to 2 do;
> 
> a1h := Generate(float(range = 0.1316881e-2 .. 0.1359706e-2)); a1f := Generate(float(range = .317149811 .. .327463626...

I have a 6 x 6 matrix. I want to employ Cramer's rule to solve Gx=Θ. I need to sequently substitute column Vector Θ into the matrix columns. I can't get this to work. I have only being using Maple for a couple of weeks so still finding my way.

Hi all

Can anyone suggest ways of speeding up this code ?

div_vec := proc(a::Vector,b::Vector)
  # procedure returns the element-byelement
  # division of vector a by vector b
  local i,c:
  c:=Vector(Dimension(a)):
  for i from 1 to Dimension(a) do
    c[i]:= a[i]/b[i]:
  end do:
  return c:
end proc:

Thanks

LR

Hi. I have nodes:=7

How do i write a matrix with my first set of nodes = -1 and a second set as 1, in a diagonal form? Sort of like a identity matrix but not quite.

What I did was to write J:=Matrix([[-1,-1,-1,-1,-1,-1,-1,1,1,1,1,1,1,1]])    ####my vector will have 2 times the number of my nodes.

Then DiagonalMatrix(J)

But I then want to change my number of nodes. Could you please advice if there's a smarter way to do this please?

Hi,

I am trying to create a do loop to generate y values from a series of vectors containing the x's. In the end, I will be exporting this data to Excel, so I want to put it into a Vector.

My problem is that sometimes I have 11 x's and sometimes I only have 9 x's.

observed := rtable(1 .. 2, 1 .. 3)

for k from 1 to 2 do 

for j from 1 to 3 do 

observed[k][j] := evalf(subs(HK[1] = C1[k, 1...

The following example shows some typical computations with Householder- or reflextion matrices. Why are the second and third variants only slightly better than the first one? Could we get a real speedup without rtable/NAG/BLAS/etc. tricks?

$ maple15
    |\^/|     Maple 15 (X86 64 LINUX)
._|\|   |/|_. Copyright (c) Maplesoft, a division of Waterloo Maple Inc. 2011
 \  MAPLE  /  All...

Hi,  if i have a matrix 4x4 as

A=[I          Y        -X        aX

     bY        Z         o          o

      X^T     O^T     0         0

       o^T  O^T       0         q ]