Hi!
I have the following code:

f:=proc(x)
   local u;
   Digits:=15;
   if x>10^9 
    then 
        u:=1/x; evalf(2/Pi*arccos((u*u-1)/(1+u*u)));
    else
        evalf(2/Pi*arccos((1-x*x)/(1+x*x)))
    end if
end proc;

The advantage is that f(+infinity) is defined in this case whereas evalf(2/Pi*arccos((1-x*x)/(1+x*x))) is not for x:=+infinity. But, I would like to extend this procedure in such a way that f(1/0) or f(something) where something is infinity or a division by zero is defined and gives the same result as f(+infinity).

I added before the preocedure f above the following code:
 

NumericEventHandler( division_by_zero = proc() +infinity; end proc ):

But, it defines a global environment. I would like a local modification of the environment only inside the procedure for f.

How to solve this issue?

Best regards,

Jaqr


 

f := -ln(-1-ln(exp(x)))+ln(-ln(exp(x)))-Ei(1, -1-ln(exp(x)))+Ei(1, -ln(exp(x)))
solve(limit(diff((subs(x=q, f)-f),h), h=0) = f, q);
limit(diff((subs(x=x*h, f)-f),h), h=0);
Error, (in limit/dosubs) invalid input: `limit/dosubs` uses a 3rd argument, newx, which is missing

guess an operator called Lee, Lee(f, x) = f

solve(limit(diff((subs(x=q, f)-f),h), h=0) = f, q);

suspect q = x*h or q=x*f

See WA30 attached.  Why the error?  The variable that represents the vector is in vector form.  If I need to change this to THAXexa := ([1988.0, 1989.0, 1990.0 , ... etc], datatype=float, is there an easy way to convert the THAXexa matrix?

Thanks, Les  WA30.mw

suppose I have

g := (x-4)^2+(y-6)^2-144:

e:=expand(g)

                     e := x^2+y^2-8*x-12*y-92

How do I get from the equation of e back to g?

I have troubles with the command in the title.

When I type

InhomogeneousDiophantine([[5^.3,1.3^.5,3^.5],[1.4^.2,4^.2,3^.33]],[5^.2,2^.5],[10^(-3),10^(-3)]);

I get the following

Error, (in IntegerRelations:-LLL) must have a non-negative size in each dimension

What have I done wrong?

dear all,

i have a Maple file where I have made some calculations solving equations, and have plotted a figure. I would like to know how to process this figure in a way so that i can get the data points of the plot, in order to plot them separately in a different software such as Excel or MATLAB for example.  

 Right-click on the figure and exporting doesnt help as the options are only to export the figure to pdf, bitmap, png, etc. This is not what I want. I want to get the data of the fiogure, so that i can plot in external software (excel, MATLAB etc)
can you give some suggestions as to how to do this ? 
thanks in advance 
best regards,

Abhishek  

sys1:=-.736349402144656384 = -1.332282598*10^12*(-.99999999999999966)^po1-1.332282598*10^12*(-.99999999999999966)^po2-.735533633151605248*Resid;

sys2:=.326676717828940144 = 1.331567176*10^12*(-.99999999999999966)^po1+1.331567176*10^12*(-.99999999999999966)^po2+.325144093024965720*Resid;

sys3:=.590327283775080036 = -1.072184073*10^9*(-.99999999999999966)^po1-1.072184073*10^9*(-.99999999999999966)^po2+.589610307487437146*Resid;

Minimize(sys1, {sys2,sys3},assume = nonnegative);

complex value encountered;

how to calculate basis <1,4,0>, <1,0,4> for eigenvalue 2;

how to calculate basis <1,0,1> for eigenvalue -1;

with(LinearAlgebra):
A := Matrix([[-2,1,1],[0,2,0],[-4,1,3]]);

sys1 := Eigenvalues(A)[1]*IdentityMatrix(3)-A;

sys1 := Eigenvalues(A)[2]*IdentityMatrix(3)-A;
sys1 := Eigenvalues(A)[3]*IdentityMatrix(3)-A;

B:=[<sys1[1,1],sys1[2,1],sys1[3,1]>,<sys1[1,2],sys1[2,2],sys1[3,2]>,<sys1[1,3],sys1[2,3],sys1[3,3]>,<0,0,0>];
LinearAlgebra:-Basis(B);

but not <1,4,0>, <1,0,4> for eigenvalue 2

A few days ago I was browsing through some books in my collection, that by Gradshteyn and Ryzhik in particular. What fraction of the intregrals, series and products therein can Maple handle correctly?  Besides special functions these properties are valuable components of symbolic mathematical software.  If the answer to this question is not nearly everything in that printed compilation, this inclusion in Maple is a worthy objective.

In Maple 2015 is there a way to fit data to an exponential model and determine the goodness of fit?

Thanks in advance!

Les

I am trying to solve the particular system of partial differential equation. But I get the following error.pdsolve.mw
 

Download pdsolve.mw

Of course, with Maple.

What would be the IBC conditions for the 1D heat equation describing the temperature distribution along a circular rod with a heat source at its base?

Hi,

I have 6 by 6 Hessian matrix H. I want to check whether it is a negative definite. The rule of negative definite is "if and only if its n leading principlal minors alternate in sign with the kth order leading principal minor should have same sign as (-1)^k".

In my Hessian H, some leading principal minor of H is zero while the nonzero ones follows above rule. So negative definite test fails and Now I have to check negative semidefinite test which state that "H is negative semidefinite if and only if every principal minor of odd order is <=0 and every principal minor of even orderis >=0". So I have to check sign of every principal minor ( instead of just leading principal minor) to check for negative semidefinite of H matrix.

Can anyone help me how can I compute sign of all principal minor of a 6 by 6 square Hessian matrix.

Thanks and Regards,

Nilesh

Hello people in mapleprimes,

I want to single out omega^epsilon from and modify the rhs of the following expression
to the expression where the  the part without omega^epsilon and  another part of  omega^epsilon
are multiplied.

Y = -L*epsilon^epsilon*(1-epsilon)^(1-epsilon)*(-omega^(-1+epsilon)*k*theta+(1-theta)*omega^epsilon)/(1-epsilon-theta)

I am glad if you teach me this.

taro