[mathcad] Re: Mathcad bug or programming error?

Author: Eden Mei Posted: Mon, 28 Jan 2008 11:12:39 -0800

Looks to me like a programming error. The line immediately following the rnorm is loada the array with zeros, but you do this on every iteration, so every iteration, the array is again zeroed, until the last iteration, when columns 10 and 11 get populated but not zeroed. This is something that you don't do at all in the second program, so your claim of them being trivially different is not. Part of the problem is that you're using the same variable in two different places for two different things.
From: "Andy.Spragg"
To: Mathcad Discussion List
Sent: Monday, January 28, 2008 5:11 AM
Subject: [mathcad] Mathcad bug or programming error?

Hi folks,

The attached v11 worksheet contains two versions of a program, that I believe to be trivially different. The output from the two versions is utterly different. I spent altogether too long trying to find the error of my ways in one version, before scraping the barrel of reformulation and finding it not to be empty after all.

I seek opinions on whether the difference in output is due to Mathcad bug or programming error. If the former is the case, it is a pretty toxic bug (which may of course have long since been squashed). Can anyone please either point out my error, or test these programs in the current version of Mathcad?

Andy

[View Complete Thread]

Previous by date: [mathcad] RE: Mathcad bug or programming error?, Pergande, Albert N
Next by date: [mathcad] RE: [MathCAD] MathCAD bug or programming error?, Philip Oakley
Previous thread: [mathcad] Mathcad bug or programming error?, Andy Spragg
Next thread: [mathcad] Mathcad bug or programming error?, Andy Spragg

Ready to buy?

Mathcad: single user licence

Add to shopping basket

$ 1,195.00

Upgrade to Mathcad 14 from version 12 or 13

Add to shopping basket

$ 325.00

Upgrade to Mathcad 14 from version 11, 2001i, 2001 or 2000

Add to shopping basket

$ 425.00

Featured Downloads

Mathcad 14 demo

Mathcad 14 Brochure

Mathcad or Excel?

Mathcad Customer Story: Man B&W Diesel

Mathcad Customer Story: Stork Fokker Aerospace

Mathcad White Paper - Moving beyond the limitations of spreadsheets

Product Reviews

"Our work ranges from complex medical imaging research to large-scale mapping and diagrams and we need a tool that is able to handle anything we investigate. With Mathcad, we are able to manipulate and analyse our data quickly while at the same time documenting our work, for sharing and publication. We also use it for pilot studies conducted in support of research grant applications. It is an end-to-end tool for research and development."
Dr. Kenneth Castleman, President of Advanced Digital Imaging Research (ADIR), Houston, Texas

"Mathcad is an integral product for my work... With Mathcad, itís easy to disseminate design calculations because the documents look like real math. Thereís very little I canít do in Mathcad. The main benefits come from the format, which resemble a typed set of calculations. These programs are easier to develop by engineers and easier for others to follow and review since the logic is expressed in a familiar manner. The format is what places Mathcad head and shoulders above other programs of a similar function."
Andre Pavlov, Structural Engineer, Florida Department of Transportation