I frequently have a problem where evalf does not fully evaluate an expression.   First of all it stops at constant expressions.  For example,  "evalf(pi)" does not give me "3.14..." it just says "pi".

Also, it sometimes does not finish evaluating expressions.  For example,

 

Are there any ways to overcome these issues?

I don't understand what I'm doing wrong with the plot command...a screenshot shows best:

 

Hi

 

I have a Maple question.

 

List 5 integers that are congruent to 4 modulo 12

 

I already know the answer.

 

Here are some of the list of integers 4, 16, -8, 1204, and -7016360

 

How do you I use Maple to generate list of integers that are congruent to 4 modulo 12

 

If I use 4 mod 12 in maple the result is 4.

 

Any assistance will be highly regarded.

 

Take care

 

 

I have 103 tables ( aal_l,  abf_l  etc )  which each has columns D, T, O, H, C  etc 

I want to exctract column C for all 103 table and store the result in a matrix

 

I know how to extract column C for one table

 

convert(connection:-ExecuteQuery("select C from aal_l", 'output' = Array), Matrix)

 

but how can it be done for multiple tables ...?

 

please help me here:

i want to evaluate the integral:

int(exp(-xi^2*(3*n+xi)/(6*n^2+6*xi*n+xi^2)), xi = -infinity .. infinity)

thanks

 

How do I enter a piecewise multivariate function in maple?

 

Thanks in advance

Lets say I need to add, as an example, 3 times row 1 to row 3.  The matrix is 3x3.  I assume I have to be using the with(LinearAlgebra); first and then I can set up the matrix, but I am lost after that.

Thanks for any help.

Hello,

 

I'm a prime in maple, I have got a problem while trying to solve the following PDE system of equations

declare:=(T(x,y),v(x,y),P(x));
                  declare := T(x, y), v(x, y), P(x)

> sys1:=[10^6*v(x,y)*diff(T(x,y),x)-0.1*diff(T(x,y),y,y)-10^3*diff(v(x,y),y)^2=0,diff(v(x,y),x)=0,-diff(P(x),x)+10^3*diff(v(x,y),y,y)=0];

>IBC = {v(0, 0.2) = 150, v(0, -0.2) = 150, T(x,0) =400, T(0,0,2) =300,P(0.3)=0.1 };

I have some 'discrete' data which I wish to analyze with Maple.  For example, I have

Hi experts, I want to make a loop. Each time the function f should be changed according to n and m. The values that I obtain with Powell (not important for the undertstanding of the problem) should be put into the matrix A[n,m] > List := Powell(f, Xmin0); [-587.000914326964951, [-0.344030213998255226, 100.344030214880177], 12, 134] > m:=1; n:=1; for n to 3 do for m to 3 do end do end do; m:=m+1; n:=n+1; f := proc (Q1, Q2)->m*Q1+n*Q2 end proc; A[n,m]:=Powell(f); # not important for the understanding of the problem

Hi,

in Maple 12 (worksheet mode), the box Maple draws around a plot to allow the user to resize the plot using the mouse appears in all my plots far too big if I label the axis. Before labelling the axes, the box has the appropriate size, but as soon as I label the axis, the box becomes far too big resulting in my plot being very small while the bos goes from one end of the screen to the other.

Any help on that?

Thank you very much in advance,

Ben

Hi,

 

in Maple 12 (worksheet mode), the tickmark-option does not work: I enter in a plot3d-command (this command works otherwise) axis[3]=[tickmarks=5] in order to get 5 divisions on the z-axis.

 

The error message is "Error, (in plot3d) incorrect value for option gridlines: 5".

 

The workaround of tickmarks=[5,5,5] works. Other axis-options work, e. g. axis[3]=[color=green] .

 

Any help on that will be appreciated.

 

Many thanks in advance,

Ben

Hi, obviously a very simple question, but not for me: I plot 3 graphes into one plot by : plot1 := plot(pts, x = 0 .. 5, y = 0 .. 1000, style = line, color = red); plot2 := plot(pts2, x = 0 .. 5, y = 0 .. 1000, style = line, color = blue); plot3 := plot(pts3, x = 0 .. 5, y = 0 .. 1000, style = line, color = green); G := textplot({[1, 1, "function"], [.5, .75, "derivative"]}); display(plot1, plot2, plot3) I tried to use texplot to lable the achses but it did not work. Is there another way to do it?

 

I loaded a 1600*3 matrix into Maple 12  from my mysql datbase on my computer and it took 3 minutes to load it .

I assume that the speed will be increase significantly if I had a fast internet connection ( both up and down ).

My Internet connection (tcp / ip) is extremly slow !!    Is this correct ?   Are there any other way to speed up the data exchange ?

 

Hi experts, I am producing a List X[n]. After that I just want to plot the values X[n] := [n, P[n]] with n on the x axw and P[n] on the y axe. for i from .1 by .1 to 5 do n := n+1; P[n] := (i*2+3*i^2) X[n] := [n, P[n]] end do; X[1] Unfortunately I get the error message and an empty plot: Warning, unable to evaluate the function to numeric values in the region; see the plotting command's help page to ensure the calling sequence is correct