Bug Report M15: symbolic processor hangs and crashes Mathcad

[StuartBruff]

Reference message http://communities.ptc.com/message/182208#182208 and the attached volume of revolution integral worksheet.

The symbolic processor hung when trying to evaluate the 'shuttle external tank' integral, eventually crashing with a MuPad DLL Kernel error 1321, which, following OK, gave C++ runtime error R6025.

Mathcad Version:

Mathcad 15.0 (M005 [MC15_M005_20101105])

System:

OS: Windows 7 Ultimate 32-bit

Processor: Athlon x64 2.6 GHz

RAM: 4 GiB (3.25 GiB usable)

[AlanStevens]

It works ok if you disable the line containing the Heaviside functions!

Alan

[StuartBruff]

AlanStevens wrote:

It works ok if you disable the line containing the Heaviside functions!

Alan

Yes, but it doesn't appear to be the Heaviside expressions per se that are causing the problem, it's the second half of the integral as a whole (..+1/5().

The whole integral evaluates correctly symbolically over the actual limits. The first half of the integral evaluates symbolically. The 2 halves of the second expression (1/5 sqrt(...) ... and (Phi()-Phi)) (ie, the Heaviside functions) evaluate OK independently; it's their product that MuPad seems to be having difficulties with ... it was still merrily chugging away after half an hour.

Note that I developed this worksheet in M13 and it was fine in Maple. M11 whizzed though the whole sheet like a rat up a drainpipe. ... if only M11 had had local functions <sigh>

Stuart

[AlanStevens]

AlanStevens wrote:

It works ok if you disable the line containing the Heaviside functions!

Alan

On second thoughts - no it doesn't! The routine simply picks up an f(x) defined before the shuttle tank example. If you turn the piecewise definition of the shuttle tank f(x), which appears at the start of the section, into an assigned function, the processor still has problems (I don't know if it stops with an error message - I got bored waiting!).

Alan

[VladimirN]

Stuart,

And how much time passed before there was this error? I could not wait for this error message (test it on Mathcad 15 M010, WinXP SP3 ).

[StuartBruff]

VladimirN. wrote:

Stuart,

And how much time passed before there was this error? I could not wait for this error message (test it on Mathcad 15 M010, WinXP SP3 ).

Vladimir,

At most a couple of hours (I went out to the Pub while it was running) and at least 45 minutes (I had it going while I did something else, then got bored waiting and interrupted it to do some more Mathcadding)

Stuart

[VladimirN]

Stuart,

I sent a report about this bug/error to PTC's technical support. I will answer when I receive some information.

[VladimirN]

This issue reported as SPR 2130072 (Severity: High).

[StuartBruff]

VladimirN. wrote:

This issue reported as SPR 2130072 (Severity: High).

Спасибо, Владимир. 🙂

Stuart

[VladimirN]

You're welcome.