---
# System prepended metadata

title: 'PR of feature: Mdst_vee2 info in b2bii conversion'

---

# PR of feature: Mdst_vee2 info in b2bii conversion
### About work flow
1. Create JIRA tickets: (take BIIANA-143 as reference)
    - Projects: Belle II Analysis
    - Component: None
    - assignee: me
    - priority: Major
    - description: 
        1. Add `Mdst_vee2::chisq()` info via `extraInfo` interface.
            - `extraInfo(chiSquared)`, `extraInfo(ndf)=1`, `PValue`
            ![](https://i.imgur.com/Nggg0UO.jpg)
            - Where: around https://stash.desy.de/projects/B2/repos/software/browse/b2bii/modules/B2BIIMdstInput/src/B2BIIConvertMdstModule.cc#718
        2. hits number and hits pattern variables associated with KS0 objects:
        `hit_svd`, `nhits(3)`, `nhits(4)`
        ![](https://i.imgur.com/z45Ydcl.png)
            + `nhits(3)`, `nhits(4)`: I think what I expect to do finally is implemented here! (the mask of the SVD hits) And what I use is followed the Belle standard: r-phi ≥ 1 hit, r-z ≥ 2 hits. But I still not comprehend the bit-shifting algo. here, and also how it can be access in the BASF2 steering script. I will try to understand this first.

2. Local repo:
    I have cloned one in my KEKCC account. But I'm not quite sure how would the change be merged into the central branch. Below I just draft a bit my _imagination_, please correct me if I'm wrong, thanks:
    - Create a new branch that based on **light-2002-janus**, by one of mentioned ways.
        - Create PR branch from JIRA, it seems to me the branch name would be taken care automatically (?).
        - `git checkout tags/light-2002-janus -b feature/XXX`
    - After modification and testing, I'll have to commit and push the developing branch and ask to merge into **light-2002-janus**.
3. About BASF2 module:
    - Compiling: do `scons` in `b2bii/modules/B2BIIMdstInput`
    - Testing: Should I add a testing script to validate the variables of `Mdst_vee2` are corrected restored in BASF2 ntuple?
    - Check syntax: `b2code-style-check`
    - Change log: `b2bii/doc/whatsnew-since/release-04-01.txt`, `whatsnew.rst`


(in development/)
```bash
b2setup light-2002-janus
scons
```

(in my source code)
```python
from ctypes import cdll
cdll.LoadLibrary('/sw/belle/local/neurobayes-4.3.1/lib/libNeuroBayesCore_shared.so')
basf2.register_module('B2BIIConvertMdst',shared_lib_path='/gpfs/home/belle2/ycchen/development/modules/Linux_x86_64/opt/libB2BIIMdstInput.so')
```
