[Numpy-discussion] Proposal for matrix_rank function in numpy

[Bruce Southey]

On 12/15/2009 12:47 PM, Alan G Isaac wrote:
> On 12/15/2009 1:39 PM, Bruce Southey wrote:
>    
>> +1 for the function but we can not shorten the name because of existing
>> numpy.rank() function.
>>      
> 1. Is it a rule that there cannot be a name duplication
> in this different namespace?
>    
In my view this is still the same numpy namespace. An example of the 
potential problems is just using an incorrect import statement somewhere:
from numpy import rank
instead of
from numpy.linalg import rank

For a package you control, you should really prevent this type of user 
mistake.


> 2. Is there a commitment to keeping both np.rank and np.ndim?
> (I.e., can np.rank never be deprecated?)
>    

I do not see that is practical because of the number of releases to 
actually remove a function.
Also the current rank function has existed for a very long time in 
Numerical Python (as it is present in Numeric). So it could be confusing 
for a user to think that the function just has been moved rather than 
being a different function.

> If the answers are both 'yes',
> then perhaps linalg.rank2d is a possible shorter name.
>
> Alan Isaac
> _______________________________________________
>    
0

Actually I do interpret rank in terms of linear algebra definition, but 
obviously other people have other meanings. I


Bruce