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### display value of integrer when stop test is verif...

March 14 2014
0 2

Dear all

I want to display the value of k   for which the stop test is verified. Thanks for your help.

epsilon:=(y0,N)->evalf(abs(

testerror:=array(1..75);
for k from 2 by 2 to 50 do
testerror[k]:=data[RK3][k][2];
if testerror[k]<=0.0001 then break; end if; end do;

### Can you use solve for multiple data points?...

March 05 2014
1 4

Hi, the title isn't great as I didn't know how to describe this really. I need to solve the following equation for b:

y = (1-exp(-x*b))/(1-exp(-50*b))

When I put a value for y in, this is fine and fsolve gives me a numeric real solution. However, even when using RealDomain, it does not give me a real solution if I leave y as it is, and instead gives a 'RootOf' solution, which I don't really understand. This is the same whether using solve or isolate:

b=-(1/50)RootOf(_Zx-50ln(-y+ye^(_Z)+1))

I have the values of x and y for multiple data points and can put them in an nx1 matrix. Is there a way to replace x and y with matrices (with real numbers in) and solve for each set of points for b (ie there would be n values of b)? Obviously I could go through and put in each value of x and y but this would take ages, so was just wondering if there's a quick way to do this.

I have tried by simply putting matrices instead of the letter but get the error:

Error, invalid input: exp expects its 1st argument, x, to be of type algebraic, but received Vector(50, {(1) = -50*b, (2) = -49*b,...

James

### for loop for matrix...

October 28 2013
1 1

Find a loop do define these matrices, even for large values of n. Record the Matrix Mn

all i,j=1,2,13,..,n for example

N := `<|>`(`<,>`(1, 2), `<,>`(2, 2))

P := `<|>`(`<,>`(1, 2, 3), `<,>`(2, 2, 3), `<,>`(3, 3, 3))

Q := `<|>`(`<,>`(1, 2, 3, 4), `<,>`(2, 2, 3, 4), `<,>`(3, 3, 3, 4), `<,>`(4, 4, 4, 4))

### Solve Product of Function With some variables...

October 15 2013
2 4

Dear All,

I need your help, what function in Maple must be used to find the different form of this function

into this function

### length of output exceeds limit of 1000000...

August 06 2013
1 3

hi

I have a program with system of equations in wich my equations are in 8 matrices (4x4) with 64unknown parameters

i have run it but after 10 minitutes maple gives this massage:

"length of output exceeds limit of 1000000"

is there any way to solve this problem?

### How to solve a set of linear and nolinear equation...

June 08 2013
2 7

I have total nine equations,out of which some are linear and some of them are nonlinear.I am a new user of maple.The nine equations are

c2+vc = .34,

c2+c3 = .519,

t8+c3-c4-vc = .132,

t1+t5-c2+0.0435=0,

t1-t2-c2+c3-1.334*vc = 0,

t2+t6-c3-c4+0.0435+1.334*vc=0,

-112.5*t1+112.5*t5+300*c2^2+1000*vc = 38.25,

112.5*t1-112.5*t2-300*c2^2+300*c3-300*c3^2-2000*vc+23.4 = 0,

-112.8*t8+112.5*t2-112.5*t6+300*c4^2-300*c3+300*c3^2+1000*vc+14.85 = 0

### How do I plot the perpendicular plot symbol (or ri...

September 15 2012
0 5

Hi, I am creating a plot to demonstrate symmetry about the y=x axis, and I want to show that the line segment connecting two points is the perpedicular bisector of the line y=x. I have plotted y=x, the two points, and the line segment connecting those two points. How do I plot the perpendicular symbol (or right angle symbol) that is connected to the lines and shows that they are indeed perpendicular?

### dsolve: additive constants of integration lost...

September 07 2012
0 0

Hello,

I'm solving a system of 3 second order ODE's for 3 unknown functions, using dsolve. But in the output, I receive various sets of solutions which contain only 3 constants of integration. A friend solved the same system but in Mathematica, and received more constants of integration.

I guess this has to do with the issue that Maple omits additive constants of integration almost everywhere.

Is there some solution? i.e. some way of using...

### Couple system of equations using loop structure...

January 22 2012
1 1

Suppose I have a system of three coupled equations as:

eqn[1] := a*x+b*x^2+c*x^3

eqn[2] := a1*x+b*x^3

eqn[3] := a2*x^2+b2*x^3 = a*x^2

If I simply write

eqs :=( eqn[1], eqn[2], eqn[3])

the equations get coupled.

1. Can I do it using loop structure?

2. Secondly, after coupling suppose I want to collect coefficoent of x, x^2 and x^3 from three equations ang get the equation in form

eq[0]:=a=0,a1=0

### Inverse of trigonometric symbolic 6x6 matrix...

November 24 2011
0 1

Hello,

i am currently trying to get some equation of motions. For this i have to invert a matrix which looks like this:

A = GL * M * GL.'     (6x6)

M is the massmatrix. GL is a matrix with kinematic constraints because i am working on a closed loop subject. The problem is that GL consists of symbolic trigonometric terms which i can't replace with numbers. Because of the multiplication with the transpose and the massmatrix the elements...

### Units Package doesn't handle Celsius to Kelvin?...

October 13 2011
0 3

I put Celsius in my equation and I get the wrong answer even though I've loaded the Units Package:

I have to put in the conversion to Kelvin by myself to get the right answer:

What am I doing wrong?

Edo

### Plotting Systems of Equations...

September 02 2011
0 3

Hello all-

I have a system of equations, something like:

X1+X2+X3=1

and then I have seperate equations such as:

X3=T*X1^2*exp(.12/T) and so on

I'd like to make a plot of X1,X2,X3 as a function of T.  How can I do this?

### why does evalc give csgn?...

July 17 2011
0 1

Hi,

I am trying to simplify the expression s as given below. (I am not sure why it comes up with all the vector caclulus notation in it but it should display okay when you enter it)

Because of the presence of the exponential imaginary fucntions I thought evalc might be useful but when I use it I get a huge expression with csgn appearing in it. To my knowledge csgn appears when assumptions are not correctly specified - is this so? I can't see any assumption...

### Min and max of x axis when using plots[pointplot]...

June 08 2011
1 5

I am getting bcak into MAPLE after being away for a while, so this might be a trivial question, but...

I am using plots[pointplot] to plot a series of points.  The default min and max values on the x and y axes of the plot are the corresponding min and max values of the x(first) coordinates and y(second) coordinates of the points.  I can change this by left-clicking on the plot and adjusting the axes properties, but I am wondering if it would be possible...

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