Items tagged with undefined


Can someone answer why i get Float(undefined) while computing integral

Here is my example





alpha0 := .3;



R := .1;



sigma := 636;



Kfc := 101;



Ksc := 9;



E := 2*10^5;



`δth` := 2*10^(-7);



`δc` := 0.8e-1*10^(-3);



p := 400;



`lδz` := 12.1*10^(-3);



lKz := 20.3*10^(-3);



eta := 10^(-5);



l0 := 0;



xi := p/sigma;



KImax := evalf(p*sqrt(Pi*l));




`Nδ` := evalf(E*sigma*(int((-xi^2+1)*(-KImax^2+Kfc^2)/((KImax^2-Ksc^2)*((-R^4+1)*(KImax^2+Ksc^2)+eta*E*sigma)), l = l0 .. `lδz`))/alpha0);


















Thanks in advance

when a term in the evaluation of some calculus functions particularly, i sometimes arrive at output in the general form as follows:


Algebraic expression + undefined


i am just wondering if there is a function i can call that will return the specific details as to what error the term "undefined" placeholder has stored im assuming such information is held, ie is it undefined as a consequence of the limits either side not being equal to one another or is it a 0/0 evaluation.

Having a function where the value is for example only defined when abs(x) <= 1, then how can I specify that the value is otherwise undefined, the replacing "How_to_specify_undefined_value" below?

hi.i am a problem with calculate numeric integral.

please help me




This question is related to and , however I have not been able to apply the solutions given there to my problem.

I have a set of points given by

and certain function value points given by

where e1 is the function I am approximating.


I come up with my piecewise function.

When I do diff(e4,x), however, the points at the nodes show "float(undefined) x=0.2..."(the node).

As it turns out, the value of the derivative on the left of the node is not equal to that of the right side by a factor of 10^(-7), in other words, numerically unimportant but high enough for maple to realise it is not the same number. How could I tell Maple that I am happy choosing, for example, the value given by the function on right side of the node?

I welcome any suggestions.

Many thanks in advance.

Hello everyone, 

I have a question regarding my Spline interpolations. I am not an expert on the theory there, but the maple help tells me that the first derivative of an 3rd degree spline interpolation should exist at the knots. But a derivation returns "undefined" at some of the knots instead. Here is my example:

x(t):=Spline([[0, 0], [1, 1], [2, 2], [3, 2.2], [4, 1.8]],t,degree=3);


x(t):=piecewise(t < 1, .953571428571429*t+0.464285714285714e-1*t^3, t < 2, -0.9286e-1+1.09285714285714*t+.139285714285714*(t-1)^2-.232142857142857*(t-1)^3, t < 3, .65000+.675000000000000*t-.557142857142857*(t-2)^2+0.821428571428571e-1*(t-2)^3, 2.77857-.192857142857143*t-.310714285714286*(t-3)^2+.103571428571429*(t-3)^3);




piecewise(t < 1., .953571+.139286*t^2, t = 1., Float(undefined), t < 2., .814286+.278571*t-.696429*(t-1.)^2, t = 2., Float(undefined), t <= 3., 2.90357-1.11429*t+.246429*(t-2.)^2, 3. < t, 1.67143-.621429*t+.310714*(t-3.)^2);


Not defined at t=1 and t=2. Is it possible to get an interpolation of which the first derivative exists at every point? Thank you very much!



I'm pretty new to Maple and I can't figure out how to input angles in degrees and radians in Maple 16 and in Maple Calculator.


E.g. How could I type 58 degrees, 28 minutes, 18 seconds?


Thanks in advance for your help!



Say for a complicated function f(x), there are 10 solutions. I want to check for any of the solutions, the matrix R is defined or not.


Is there a way to force execution like the following ones?


for i from 0 to 3 do
end do;


I think the problem is that, Maple stops immediately when it's undefined. But the following terms could be defined.

Or is there a way to put this check into "solve"? That's

> solve(f(x),x, "some way of making sure that the solution has to be defined for the matrix R" )



Is there a way to achieve this?


I keep getting an error about the while. It is calling it an invalid if statement.  It may relate to semi colons, but I cannot find any errors myself. Please help.


local ix,iy,i,j,i0,i1,j0,j1,k;      

local count,wgt,top,bot,hp;      



for iy from 1 to n do      

for ix from 1 to n do           

if (IR(ix,iy)=0) then                

i0:=max(1,ix-rwin);  i1:=min(n,ix+rwin);                

j0:=max(1,iy-rwin);  j1:=min(n,iy+rwin);                 


while (k<mink )do                              

if(i0>1) then                                       

i0:= i0-1;                                       

k:= k+ add(IR(i0,j),j=j0..j1)                              

end if;                              

if(i0<1) then                                        


k:= k+ add(IR(i0,j),j=j0..j1)                              

end if;                              

if(j0>1) then                                        


  k:= k+ add(IR(i,j0),i=i0..i1)                         

  end if;                           

 if(j0<1) then                                

 j0:= j0+1;                                         

k:= k+ add(IR(i,j0),i=i0..i1)                             

end if;                         

end do;                  

top:=0;  bot:=0;                

for j from j0 to j1 do                

for i from i0 to i1 do                      

if (IR(i,j)<>0) then                           




end if;                

end do;                

end do;                


end if;      

end do;      

end do;  

end proc:

So this is the errorcode I get and my code is

> r := (x1, y1, x2, y2) options operator, arrow; (sqrt((x2-x1)^2+(y2-y1)^2))^2
> hreg := (A, C, x) options operator, arrow; A*x+C
> hpconf := (Q, x1, y1, x2, y2) options operator, arrow; Q*(1/4)*ln(2.25*b*K*t/(S*r(x1, y1, x2, y2)))/(3.14*K*b)

> he1 := (x, y, C) options operator, arrow; hreg(A1, C, x)+hpconf(Q1, x, y, xp1, yp1)+hpconf(Q2, x, y, xp2, yp2)+hpconf(Q3, x, y, xp3, yp3)+hpconf(Q4, x, y, xp4, yp4)
> C1 := solve(he1(-75, 0, C) = 20, C);

> plot3d(he1(x, y, C1), x = -75 .. 75, y = -75 .. 75, style = surfacecontour, axes = box);

I have defined all the constants, and squareboxes shouldn't be needed for the plot, right?


Dear Maple Users,

I'm beginner in Maple.

I have this system of Pde:

with lambda experimental parameter and n,c,v dependent variables. I write this on Maple but I read on internet that the solution "float(undefined)" is an error.

I will insert this initial condition: c(x,0)=0,n(x,0)=0.4

Thanks everybody

Hallo guys,

I am newbie in Mapple, i could not solve the problem yet, here is my little function. I want to estimate beta with the Maximum Likelihood Estimation with Weibull: 

> MaximumLikelihoodEstimate(Weibull(beta, eta), F1); F1 := Vector([1500, 1750, 2250, 4000, 4300, 5000, 7000]);
print(`output redirected...`); # input placeholder
[beta = HFloat(HFloat(undefined)), eta = HFloat(HFloat(undefined))



May someone help me why i just get HFloat(undefined)  ?


Kind regards

Just came across this

Press esc twice then enter.  Maple becomes unresponsive. 



Hi, again:

Is there a way to connect Maple with Sqlite?

Thanks in advance



I am dealing with second order linear differeantial equations for RLC and forced RLC circiuts.

I am having trouble with plotting a solution curve in the phase plane.


> restart;

with(plots); with(DEtools);

L := 10; R := 20; C := 1/100;

de1 := diff(x(t), t) = y(t);

de2 := L*(diff(y(t), t))+R*y(t)+x(t)/C = 0;


DEplot({de1, de2}, [x(t), y(t)], t = 0 .. 5, [[x(0) = 10, y(0) = 0]], stepsize = 0.5,

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