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Errors converting from single complex to mp complex and back

Owen 9 jaar geleden • bijgewerkt door Pavel Holoborodko 9 jaar geleden • 3
I'm getting errors when I try to convert a single-precision complex variable to mp type and back. For example:
>> x = single(1 + i)
x =
1.0000 + 1.0000i
>> x = mp(x)
x =
6.94449606095542138733663817572487e-310 + 5.263544247120890312873936353273975e-315i

Due to the nature of the application I'm working on, I can't get around this by using a string, e.g. mp('1+i'); I have to convert from a single-precision variable. Presently I'm getting around this by casting the variable to double before passing it to mp, e.g. x = mp(double(x)), but I'd like to not have to do that.

In addition, when I try to cast from mp to single, the variable gets cast to a double instead. For example:
>> x = mp('1+i')
x =
1 + 1i
>> x = single(x)
x =
1.0000 + 1.0000i
>> whos
Name Size Bytes Class Attributes
x 1x1 16 double complex

Presently I'm getting around this issue by calling single() twice, e.g. x = single(single(x)), but again, I'd like to not have to do that.

I'm using MATLAB version 8.4.0.150421 (R2014b) and mp version 3.8.5 Build 9059.
Started
Pavel Holoborodko 9 jaar geleden
Dear Owen,

Both bugs are confirmed and will be fixed in next updates.
Thank you very much for reporting!

Until then, you can try using the following workarounds:

A. For 'mp' to 'single' conversion:

Replace the following line in mp.m (line #1146):
r =  mpimpl(9000,x);
with 
r = single(mpimpl(9000,x));
B. For 'single' to 'mp':

Please insert this code after #667 line in mp.m:
           if nargin == 1
            if isa(x,'single'), x = double(x); end;
           end;
Pavel Holoborodko 9 jaar geleden
These issues have been already fixed in Windows version - you can download it from our website the usual way.
Updates for GNU Linux & Mac OSX follow (I know you probably use the GNU Linux version).
Fixed
Pavel Holoborodko 9 jaar geleden
The issues have been fixed on all platforms.

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