Add overloaded `prod` method

[marcsous]

Hi Dylan,

A little bug, invalid imaginary index input not detected:

>> a=MappedTensor(1);
>> a(i)=1
Error using MappedTensor>ConvertColonsCheckLims (line 1861)
*** MappedTensor: Index exceeds matrix dimensions.
Error in MappedTensor>mt_write_data (line 1715)
   [vnLinearIndices, vnDataSize] = ConvertColonsCheckLims(sSubs.subs,
   vnTensorSize, hRepSumFunc);
Error in MappedTensor/subsasgn (line 503)
            mt_write_data(mtVar.hShimFunc, mtVar.hRealContent, subs,
            mtVar.vnOriginalSize, mtVar.strClass, mtVar.nHeaderBytes, tfData ./
            mtVar.fRealFactor, mtVar.bBigEndian, mtVar.hRepSumFunc,
            mtVar.hChunkLengthFunc); 

Also I wonder if you would consider adding these utility functions?

length
ndims
mean
prod
isfloat
isinteger

>> a=MappedTensor(1,'class','single');
>> isfloat(a)
ans =
     0
>> a=MappedTensor(1,'class','int8');
>> isinteger(a)
ans =
     0

Also, would you consider setting properties (SetAccess = private, GetAccess = public) so we can see the internals of the class using details() function?

Last thing, this is a little tricky, what should MappedTensor return for class()? Should it be of the contained values (single, double, int8, etc.)? I'm asking since a lot of (my) code checks for class and so MappedTensors require extra handling.

Thanks for your help!
Mark

[DylanMuir]

Hi Mark,

Ok, I added a few things.
mean works in any case, since it's just a matlab function.
I added length, isinteger, isfloat, isnan.
prod requires more work; I haven't done that now. Feel free to adapt sum, if you have more time :)

I think class(obj) should return MappedTensor, because sometimes you really need to know that. But if you instead use isfloat, isinteger, islogical, etc. then you should be fine.

[marcsous]

Thanks Dylan, I will look at prod over the weekend. Great, great piece of software. It's made a big difference to my work.

[farhi]

Hi all,
a new version of the MappedTensor has been published at https://gitlab.com/soleil-data-treatment/soleil-software-projects/MappedTensor. It now has load/save methods, as well as prod.