Simplify[Sqrt[x^2], x > 0]

[fja-pedraza]

Description

The expression Simplify[Sqrt[x^2], x > 0] does not result in x, as expected

How to Reproduce

In Django go to a new notebook cell and enter the expression: Simplify[Sqrt[x^2], x > 0]
Simultaneously press the Shift+Enter keys

Output Given

The obtained result is: Sqrt[ x ^ 2 ]

Expected behavior

The expected result is: x

Your Environment

Software Information
Python
Python: 3.10.12 (main, Jun 11 2023, 05:26:28) [GCC 11.4.0]
Implementation: CPython 3.10.12.final.0
Mathics3 Software
Mathics3 Django: 6.0.0
Mathics3: 6.0.2
Web Software
Django: 4.2.5
mathics-threejs-backend: 1.3.1
three.js: 146
MathJax: 2.7.9
Numeric Software
mpmath: 1.3.0
Numpy: 1.24.4
Sympy: 1.12
Optional Software
cython: Not installed
lxml: 4.9.3
networkx: 3.1
nltk: 3.8.1
psutil: Not installed
skimage: Not installed
scipy: 1.11.2
wordcloud: Not installed
Settings
Django
ALLOWED_HOSTS: []
DEBUG: True
DISPLAY_EXCEPTIONS: False
Mathics3 Django
Settings$PreferredBackendMethod: "sympy" This sets whether to use mpmath, numpy or Sympy for numeric and symbolic constants and methods, when there is a choice. Settings$QuotedStrings:
If this Boolean variable is set False, hide the quotes when the top-level value is a string.
Settings$TraceGet: If this Boolean variable is set True, 'Get' traces the lines it reads that start a new expression. Settings$UseSansSerif:
If this Boolean variable is set True, MathMLForm uses a Sans-Serif font.
System information
User Name: fpedraza
Process ID: 357
System Time Zone: -6.0
File Paths
Base Directory: /home/fpedraza/.local/lib/python3.10/site-packages/mathics
Home Directory: /home/fpedraza
Installation Directory: /home/fpedraza/.local/lib/python3.10/site-packages/mathics
Root Directory: /
Temporary Directory: /tmp
Workspace Database File: /home/fpedraza/.local/var/mathics/mathics.sqlite
Doctest Data: /home/fpedraza/.local/var/mathics/doc_html_data.pcl
Machine information
Machine Name: DESKTOP-Q6RKU5O
Machine: linux
Processor Type: x86_64
Memory Available: -1
System Memory: -1
Machine Precision: 15.954589770191003
Connection Information
HTTP User Agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/117.0.0.0 Safari/537.36
Remote User:
Remote Address: 127.0.0.1
Remote Host:

Workarounds

The desired result can be obtained with the following SymPy command: refine(sqrt(x**2), Q.positive(x))

Priority

Additional context

[mmatera]

@fja-pedraza: indeed, something good would be to improve and enlarge the number of cases that Simplify and FullSymplify are able to handle.
Here:
sympy_result = sympy.simplify(sympy_expr, measure=complexity_function)

is where the call to Sympy.simplify is done. Maybe this routine could be improved to support more general cases.