[ncl-talk] output of dgeevx_lapack
Kevin Hallock
hallock at ucar.edu
Thu Mar 2 10:36:18 MST 2017
Hi Andy,
Do you have an example script in which you’re trying to use dgeevx_lapack(), and if so would you be willing to share it?
Thanks,
Kevin
> On Feb 27, 2017, at 10:02 AM, Andy <awmiller at mit.edu> wrote:
>
> Does anyone have any feedback on how to access the condition numbers that dgeevx_lapack should be able to calculate?
>
> Thanks
> Andy
>
> On 02/20/2017 06:20 PM, Andy Miller wrote:
>> The argument I am confused by is called "sense". The Fortran description reads as follows:
>>
>> SENSE (input) CHARACTER*1
>> * Determines which reciprocal condition numbers are computed.
>> * = 'N': None are computed;
>> * = 'E': Computed for eigenvalues only;
>> * = 'V': Computed for right eigenvectors only;
>> * = 'B': Computed for eigenvalues and right eigenvectors.
>> * If SENSE = 'E' or 'B', both left and right eigenvectors
>> * must also be computed (JOBVL = 'V' and JOBVR = 'V').
>>
>> The other arguments produce reasonable results and, most importantly, change the output in a way I can follow. Changing the 5th or sense argument doesn't seem o have any effect.
>>
>>
>> On 2/20/2017 5:49 PM, Dennis Shea wrote:
>>> Offline.
>>> I am out most of the week. I have no access to a computer till later. Can u pls click on the 'dgeevx' link in the function documentation? This gives the Fortran documentation. What arguments are you asking about?
>>>
>>> Sent from my iPhone
>>>
>>> On Feb 20, 2017, at 1:57 PM, Andy <awmiller at mit.edu <mailto:awmiller at mit.edu>> wrote:
>>>
>>>> Hello,
>>>> I am running NCL version 6.3.0 on a Linux (Ubuntu) machine with a bash shell. I am trying to use the dgeevx_lapack function for the first time. The documentation includes an option to calculate reciprocal condition numbers. Enabling that option will not lead to any error messages, but I also can't find the result of that calculation. Running the command in the following three versions:
>>>>
>>>> evl = dgeevx_lapack(M,"N","V","V","N",False)
>>>>
>>>> evl = dgeevx_lapack(M,"N","V","V","E",False)
>>>>
>>>> evl = dgeevx_lapack(M,"N","V","V","B",False)
>>>>
>>>> for any given matrix M results in variables evl that contain the same number of values and are seemingly identical otherwise, too.
>>>>
>>>> How can I access the reciprocal condition numbers? Is there another ncl function I should use?
>>>>
>>>> Thanks for your help,
>>>> Andy
>>>>
>>>> --
>>>> Andy Miller
>>>> MIT PAOC PhD Candidate
>>>>
>>>> 77 Massachusetts Ave | 54-1715
>>>> Cambridge, MA 02139
>>>>
>>>> Phone: 617-253-3715
>>>> Email: awmiller at mit.edu <mailto:awmiller at mit.edu>_______________________________________________
>>>> ncl-talk mailing list
>>>> ncl-talk at ucar.edu <mailto:ncl-talk at ucar.edu>
>>>> List instructions, subscriber options, unsubscribe:
>>>> http://mailman.ucar.edu/mailman/listinfo/ncl-talk <http://mailman.ucar.edu/mailman/listinfo/ncl-talk>
>>
>
> _______________________________________________
> ncl-talk mailing list
> ncl-talk at ucar.edu
> List instructions, subscriber options, unsubscribe:
> http://mailman.ucar.edu/mailman/listinfo/ncl-talk
-------------- next part --------------
An HTML attachment was scrubbed...
URL: http://mailman.ucar.edu/pipermail/ncl-talk/attachments/20170302/be184626/attachment.html
More information about the ncl-talk
mailing list