rPIE tweaks, comment out rPIE scan position correction as it's not doing things correctly (I'll fix later).

[a4894z]

Purpose

(a) rPIE probe update is now strictly ePIE as the parameter which makes ePIE and rPIE different is irrelevant for the probe updates, (b) rPIE scan position correction has been commented out for now as it is incorrect and not effective, (c) renamed/removed some redundant variables in multislice rPIE

Approach

I'll fix the rPIE scan position correction code later or simply remove it from rPIE and LSTSQ code so that both ptycho updates schemes for the sample/probe use the same scheme for scan position updates. Also, from a recent publication of mine that thoroughly benchmarks rPIE and ePIE, we concluded that for the probe updates that rPIE and ePIE are equally effective. Since ePIE is simpler to compute, we use this now for the probe updates (rPIE is still used for the sample updates).

Pre-Merge Checklists

Submitter

• Write a helpfully descriptive pull request title.
• Organize changes into logically grouped commits with descriptive commit messages.
• Document all new functions.
• Click 'details' on the readthedocs check to view the updated docs.
• Write tests for new functions or explain why they are not needed.
• Address any complaints from pep8speaks.

Reviewer

• Actually read all of the code.
• Run the new code yourself; the included tests should make this easy.
• Write a summary of the changes as you understand them.
• Thank the submitter.

[pep8speaks]

Hello @a4894z! Thanks for opening this PR. We checked the lines you've touched for PEP 8 issues, and found:

• In the file src/tike/ptycho/solvers/rpie.py:

Line 147:40: W291 trailing whitespace
Line 180:36: W291 trailing whitespace
Line 271:41: E201 whitespace after '['
Line 271:48: E202 whitespace before ']'
Line 348:5: E265 block comment should start with '# '
Line 348:81: E501 line too long (114 > 80 characters)
Line 349:39: E201 whitespace after '('
Line 349:41: E201 whitespace after '('
Line 349:68: E202 whitespace before ')'
Line 349:77: E251 unexpected spaces around keyword / parameter equals
Line 349:79: E251 unexpected spaces around keyword / parameter equals
Line 349:81: E501 line too long (92 > 80 characters)
Line 349:91: E202 whitespace before ')'
Line 374:81: E501 line too long (118 > 80 characters)
Line 447:13: E265 block comment should start with '# '
Line 448:49: E202 whitespace before ')'
Line 448:51: E203 whitespace before ':'
Line 448:53: W291 trailing whitespace
Line 450:55: E201 whitespace after '['
Line 450:72: E202 whitespace before ']'
Line 450:81: E501 line too long (169 > 80 characters)
Line 450:110: E201 whitespace after '('
Line 450:168: E202 whitespace before ')'
Line 465:40: E201 whitespace after '['
Line 465:48: E202 whitespace before ']'