Question: Assume with subindexed variables (with/without Physics package)

Hello,

I was trying to simplify an expression using assume. However, I ended up with very long evaluation time and got an error: "Error, (in type/complex) too many levels of recursion". Here is the case:

Consider the following code:

restart:with(Physics):
simplify(csgn(a-b),assume=[a::real,b::real, a>0,b>0,a>b])

this gives 1 as expected.

However, if I run the following code:

restart:with(Physics):
simplify(csgn(a-b[2]),assume=[a::real,b[2]::real, a>0,b[2]>0,a>b[2]])

I get an error ""Error, (in type/complex) too many levels of recursion" after along evaluation. The last condition a>b[2] is causing the along evaluation time. Without it I get, of course, signum(a-b[2]), which is fine. 

If I do these tests without Physics package loaded, I get the result 1 immediately in both cases without any problem. So, something in Physics package is causing this problem. 

What is the problem? and how can I resolve this issue?

Thank you in advance.

 

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