Turn on suggestions

Auto-suggest helps you quickly narrow down your search results by suggesting possible matches as you type.

Showing results for

Auto-suggest helps you quickly narrow down your search results by suggesting possible matches as you type.

Showing results for

- Subscribe to RSS Feed
- Mark Topic as New
- Mark Topic as Read
- Float this Topic for Current User
- Bookmark
- Subscribe
- Mute
- Printer Friendly Page

Oct 26, 2017
03:49 PM

- Mark as New
- Bookmark
- Subscribe
- Mute
- Subscribe to RSS Feed
- Permalink
- Notify Moderator

Oct 26, 2017
03:49 PM

Length-1 Vector Multiplication Error

I have found an error in vector multiplication when the length of one vector is reduced to just one. It should not throw an error, but does, stating that "These array dimensions do not match", which is just ridiculous.

Of course, there are workarounds, but this should be corrected.

Thoughts anyone?

4 REPLIES 4

Oct 26, 2017
04:43 PM

- Mark as New
- Bookmark
- Subscribe
- Mute
- Subscribe to RSS Feed
- Permalink
- Notify Moderator

Oct 26, 2017
04:43 PM

Nukeman,

I agree that the symbolic processor has a bug. However, please note that the numeric processor calculates the correct product.

Oct 26, 2017
05:12 PM

- Mark as New
- Bookmark
- Subscribe
- Mute
- Subscribe to RSS Feed
- Permalink
- Notify Moderator

Oct 26, 2017
05:12 PM

Mostly correct. However, the Lev-Mar method (in genfit and Least SquaresFit) has to resolve the first derivatives of the fitting parameters. That's where I've run afoul of this problem.

Oct 26, 2017
05:13 PM

- Mark as New
- Bookmark
- Subscribe
- Mute
- Subscribe to RSS Feed
- Permalink
- Notify Moderator

Oct 26, 2017
05:13 PM

How does it fare when the vector (with the lower case letters) is reduced to a single element vector (containing just a)?

In Mathcad 11:

Luc

Oct 26, 2017
05:26 PM

- Mark as New
- Bookmark
- Subscribe
- Mute
- Subscribe to RSS Feed
- Permalink
- Notify Moderator

Oct 26, 2017
05:26 PM

Yes, Prime produces this same result. But, this is still only half right.

Thanks for checking.