at what complexity, a comparison fails ?

hello,

I had a program that worked perfectly well.
In this program modules were dynamically added,
just by putting the file in a predefined directory.

Now one of the interface mechanisms was to see if some parameter was changed in a an instance,
by comparing the value from the instance with its previous value

This went all well, untill I added a too complex variable,
then the program stopped working, without generating exceptions.

So it seems that comparing a too complex value isn't allowed.
the variable was something like:

A = [ <ndarray>, <ndarray>, ..., [<color>,<color>,...], [<float>, <float>, ... ] ]

So what I need was something like:
if A != A_prev :
... do something
A_prev = A

And this crashes, or at least it doesn't work but also doesn't generate exceptions.
It does seems to work, if A only contains 1 array.

Why am I not allowed to compare A and A_prev ??
And in general, how complex might a list be to make a valid comparison,
or what are the rules ?

thanks,
Stef Mientki


.

Relevant Pages

  • Re: at what complexity, a comparison fails ?
    ... by comparing the value from the instance with its previous value ... program stopped working, without generating exceptions. ... And this crashes, or at least it doesn't work but also doesn't generate ...
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  • Re: at what complexity, a comparison fails ?
    ... without generating exceptions. ... So it seems that comparing a too complex value isn't allowed. ... Lists are compared element wise. ...
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