I'm newbie with Mathematica, so probably my problem is very easy to be solved.
I want to solve a PDE:
The first problem is that the program is not substituting the values inside w[x,y] and its second derivatives, to use them as boundary conditions.
It tells me that Tag Equal in ((w1^(2,0))[x,y]==0)[x,y] is Protected
The other problem is that it gives me also another type of error:
"{NDsolve[{(w1^(0,4))[x,y]+(w1^(2,2))[x,y]+(w1^(4,0))[x,y]==0,{w1[0,y]==0,w1[5,y]==0,((w1^(2,0))[x,y]==0)[0,y]==0,((w1^(2,0))[x,y]==0)[5,y]==0},{w1[x,0]==3,w1[x,5]==3,((w1^(0,2))[x,y]==0)[x,0]==0,((w1^(0,2))[x,y]==0)[x,10]==0}},w1[x,y],{x,0,10},{y,0,5}]} is neither a list of replacement rules nor a valid dispatch table, and so cannot be used for replacing."
Thank you in advance.
I made some changes.
First of all I fixed the boundary conditions because they had a problem.
Moreover I changed also the equation.
Now it still gives me the error:
"{NDsolve[{(w^(0,4))[x,y]+(w^(2,2))[x,y]+(w^(4,0))[x,y]==2,{w[0,y]==0,w[5,y]==0,chix[0,y]==0,chix[5,y]==0},{w[x,0]==0,w[x,10]==0,chiy[x,0]==0,chiy[x,10]==0}},w,{x,0,5},{y,0,10}]} is neither a list of replacement rules nor a valid dispatch table, and so cannot be used for replacing."
If we succeed in fixing this problem, Mathematica should give us a non zero solution.
Thank you very much!
Rewriting it, it doesn't provide any solution. And it also gives no errors. It looks like it is not even substitutiing the boundary conditions. I decided to change them, solving in this way another kind of problem. It still doesn't work. I think that it is very strange, since if the boundary conditions were wrong it should have provided either an indeterminate condition or an impossible one. Any idea?
Thank you very much for your help!
I'm somewhat new to ruby and I was wondering how bad of an idea would it be to pass along state in an exception? For example have an exception, that holds a list with all errors, that occured during a computation. Or would it be better to have the computation function explicitly return two things, a list of results and a list of errors if I know that things can go wrong?
It sounds like you are trying to reimplement Haskell's Data.Either or Control.Monad.Error in Ruby. Someone already did that: https://github.com/pzol/monadic#either
I remember seeing somewhere that you can specify which dll to get the address of symbols so that one can use that variable in the watch window. I can't for the life of me remember where I saw this. The best that I can come up with is Format Specifiers in C++.
The reason I want this is so that I can see the visibility status of a window and MSVS keeps saying that identifier "IsWindowVisible" is undefined.
I was trying to use something like the following in the watch window:
::IsWindowVisible(m_hWnd),user32.dll
Using:
this->IsWindowVisible()
results in Function CWnd::IsWindowVisible has no address, possibly due to compiler optimizations. which is why I'm trying to use the win32 call. Ideas?
http://msdn.microsoft.com/en-nz/library/y2t7ahxk.aspx
Haven't tried it, but it seems to me that IsWindowVisible(m_hWnd) should work, or maybe IsWindowVisible(this->m_hWnd).
I'm a noob and trying to convert an example from a book into an app I can use.
The sample app is a modified version of the contacts application and it works.
I've done some further modification, and the search no longer works. It sigabrts on the following line
self.filteredAnswercards = [flattenedArray
filteredArrayUsingPredicate:predicate];
I'm stumped.
my head is bloody from beating it against my keyboard.
ANY help is massively appreciated.
Thanks.
My suggestion was to wrap the line that crashes inside a #try/#catch block and, inside the catch, log the exception and the result of the exception's callStackSymbols method.
For the record, part of the problem with the 4.x versions of Xcode is that they are much worse than 3.x versions at telling you where an exception is coming from. For this reason, getting familiar with tricks that make a program or the debugger tell you what you need to know is very important.
I would guess that predicate is nil. Where did you assign it? Or did you never assign it?
Very hard to say without seeing more code. Sigabort generally means an exception has been thrown. You can put a break point in objc_exception_throwto get a back trace which should help highlight the cause.
If you get NO new info with the above, others have said that a full reboot of the computer can help... but I have not had a situation where I could verify this.
---- edit based on comments -----
It sounds like filteredAnswercards is nil, that will definitely cause a Sigabort. Allocate that array properly and you should be good to go.
Is it possible to have partial completions in Xcode? By that I mean if we were calling a method on a string
eg.
[string <some method here method>]
on XCode, currently if you type
[string
and hit escape, you'll see suggestions for methods you can call on the object. If I wanted to find the method which checks equality isEqualToString, I only get the suggestion if I start typing isE..., but is there a way code completion will still give isEqualToString as a suggestion if I type "equal" ie. it matches against any part of a method?
Thanks!
I'm sorry but there is no way, there aren't really any ways to change the way Xcode handles the code completion, all you can do is turn it on or off. Your best bet may be a feature request to Apple.