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How to see full text instead of skeleton <<1>>?

Posted 9 years ago

I am trying to solve system of PDE with NDSolve. and I git an error message like this

NDSolve::deqn: Equation or list of equations expected instead of ConditionalExpression[long expression with many omitted parts like <<1>> <<2>>].

My question is how to expand all these skeletons

<<1>>, <<2>>

(number in double less then and great then signs) and etc to full real values? As I understand from here this syntax


means that expression is too big and Mathematica try to make it shorter and replace some parts as


I tryied to use TotalWidth option like this

SetOptions[NDSolve, TotalWidth -> 500]
syssolution = NDSolve[{systemtosolve, ic}, 
    vars, {t, 0, 10^-6}....];

but I got an error message "SetOptions::optnf: TotalWidth is not a known option for NDSolve."

4 Replies

Thank you for your answer. I was a mistake from my side. Of course it is Z[x_]. Function if fully workinng and I printed graph of this function in this file many times. [CapitalPhi] I need to find. It is my vars for NDSolve.

Thank you for your reply. I tried to minimize my problem and I found the main reason, but I still do not know what I can do.

My code looks like this

KH := Rationalize[0.12]; 
L := 1; 
S := Sqrt[3]/4*L^2;
\[Mu] := 4*S/(WL*L); \[Phi]0 := Pi;

systemtosolve = {    D[\[CapitalPhi][t, \[Xi]l, \[Xi]r], t] == 1 +
     Cos[\[Mu] *\[CapitalPhi][t, \[Xi]l, \[Xi]r] + 
       KH*Re[Z[\[Xi]r] - Z[\[Xi]l]] - \[Phi]0]    };

ic = {    \[CapitalPhi][0, \[Xi]l, \[Xi]r] == Pi    };
vars = {\[CapitalPhi]};

syssolution =    NDSolve[{systemtosolve, ic},     vars, {t, 0, 1}, {\[Xi]r, -0.1, 0.1}, {\[Xi]l, -0.1, 0.1}];

NDSolve::deqn: Equation or list of equations expected instead of ConditionalExpression[(\[CapitalPhi]^(1,0,0))[t,\[Xi]l,\[Xi]r]==1-Cos[3/25 Plus[<<2>>]+1250000000/791 Power[<<2>>] \[CapitalPhi][<<3>>]],(((0.
-2. I) \[Xi]l\[Element]Reals&&Re[(0. +2. I) \[Xi]l]<0.208)||Re[(0. -1. I) \[Xi]l]>-0.104)&&(((0. -2. I) \[Xi]r\[Element]Reals&&Re[(0. +2. I) \[Xi]r]<0.208)||Re[(0. -1. I) \[Xi]r]>-0.104)] in the first argument {{ConditionalExpression[(\[CapitalPhi]^(1,0,0))[t,\[Xi]l,\[Xi]r]==1-Cos[Plus[<<2>>]],((Times[<<2>>]\[Element]Reals&&Re[<<1>>]<0.208)||Re[Times[<<2>>]]>-0.104)&&((Times[<<2>>]\[Element]Reals&&Re[<<1>>]<0.208)||Re[Times[<<2>>]]>-0.104)]},{\[CapitalPhi][0,\[Xi]l,\[Xi]r]==\[Pi]}}.

The problem dissappeared if I remove function Z[] This function is defined like this

Z[x_] := 2*I*Integrate[Exp[-y^2.0 + 2.0*I*y*x], {y, 0, Infinity}];

When I just calculate Z function or draw it's graph everything is fine, but NDSolve do nto like this function somehow.

Can you help me to understand, what is wrong with Z function?

Edited: misprint corrected.

Is that the actual code for the Z function? If so, it needs to be this:

Z[x_] := 2*I*Integrate[Exp[-y^2.0 + 2.0*I*y*x], {y, 0, Infinity}];

You have to put an underscore after every argument when defining a Mathematica function.

Another possible error: did you define the function \[CapitalPhi]?

POSTED BY: Jesse Friedman

Can you post some of the code you're using? That error indicates that the arguments you provided to NDSolve are incorrectly formatted.

POSTED BY: Jesse Friedman
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