Recent content by arshia

Sorry i should send you the complete code .forgot that you can't run without "lagrangeq"s &... here is the full code as an attachment... please help me as you done it well in the past, if possible...

Hi DaleSpam Can you help me about the error findroot::istol please? i recently used the code below but the error apeared : ------------------------------------------------------------------------------------------ lagrangesolveg2 = NDSolve[{lagrangeq12 == 0, lagrangeq22 == 0, q1[0] == hh4...

Thank you Dale, i don't know what the problem was but it was solved in my new run.maybe i made a mistake like the one you said... but after that, recently i wrote the code below but don't know what the problem is : NDSolve[{0.461543 Derivative[1][\[CurlyPhi]i1p][t] - 0.15287...

Hi DaleSpam how are you today? can u tell me about the error : Set::write: Tag Times in Null {0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,1,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,<<1089>>} is Protected. >> i read about it but yet don't know why it occurs? when i run my code part...

i didnt know it... Thanks for your good informations

yes but my problem is not about having solution or not, the problem is the error: InterpolatingFunction::dmval: Input value {7.33381} lies outside the range of data in the interpolating function. Extrapolation will be used. >> nowhere in my code "t" lies out of the range. my t range is 0 to 5...

i don't know what this error means(i know its definition but also know no number lies out of the range in my code) and why occurs. have you any idea for this problem?

i wrote a new code that have a limiting condition for finding roots and it works correctly in general. but i recently faced with some points that FindRoot could not find a solution for them even though in fact we know it has a solution ! my code is as below for i,j,k,l as defined ...

ok, thank you very much DaleSpam

This is a good idea but in fact in my general code i have a "for" loop that must finds this roots automatically in each loop and we know that the figure changes. then i can't define the starting point for FindRoot. have you any idea for it? regards

Hello dear Dale recently i had written a code in mathematica and used NDSolve to solve equations as below : \[Gamma] = 0.01; equ1 = \[Theta]''[t] - Sin[\[Theta][t] - \[Gamma]]; equ2 = -\[CurlyPhi]''[t] + \[Theta]''[ t] + (\[Theta]'[t])^2 Sin[\[CurlyPhi][t]] - Cos[\[Gamma] - \[Theta][t]]...

Hello dear Dale recently i had written a code in mathematica and used NDSolve to solve equations as below : \[Gamma] = 0.01; equ1 = \[Theta]''[t] - Sin[\[Theta][t] - \[Gamma]]; equ2 = -\[CurlyPhi]''[t] + \[Theta]''[ t] + (\[Theta]'[t])^2 Sin[\[CurlyPhi][t]] - Cos[\[Gamma] - \[Theta][t]]...

Thank you DaleSpam... :)

Thank you very much DaleSpam. now it works correctly but i want to know if there is a problem when it gives me the answer but also say : NDSolve::ntdvdae: Cannot solve to find an explicit formula for the derivatives. NDSolve will try solving the system as differential-algebraic equations. >>...

Ok but because of containing special characters,you must copy the code into your own Mathematica to see it correctly... lagrange\[CurlyPhi]i1= 56.8293 (Sin[\[Pi]/ 45] (0.169258 Cos[\[CurlyPhi]i1[t]] + 0.0118478 Sin[\[CurlyPhi]i1[t]]) + Cos[\[Pi]/ 45] (-0.0653683...