Questions about subscript (Vensim function)

[18811184907]

Dear James Houghton：
Hello, I am a postgraduate student from China, learning PySD 1.10.0. I have recently encountered a problem in the use of subscripts, and I would like to ask you for some knowledge about it.
It seems that there is no function in Lookup that can call a value with a subscript or assign a value directly. I'd like to know your solution and hope you have time to look at it and give some advice, your suggestions would be very useful to me. Thank you!
Fang zhe
This is the ‘.mdl’ file.

vensim.txt

This is simple code.

path = r"C:\Users\User\Desktop\all\pythonpysd\"
name = "T15"
typrname = ".mdl"
f = path + name + typrname
model = pysd.read_vensim(f, split_views=True)
print(model.doc())
print(model)

[enekomartinmartinez]

Hi @18811184907
Unfortunately, PySD current version doesn't support that feature for hardcoded lookups
However, it is implemented for external lookups. There are two possible options here:

1. Maybe the fastest is to move your lookup to an Excel file and read it with Vensim using GET XLS LOOKUPS or GET DIRECT LOOKUPS
2. Implement subscript support for hardcoded lookups, this will require rewriting how hardcoded lookups are translated to pysd.

Moreover, currently any kind of lookups accept subscript as a parameter therefore you may need to define an intermediate variable, for transform the subscripts in numeric values, e. g.:

c[age]=
	a(age_values[age])
	~	
	~		|

a(
	GET DIRECT LOOKUPS('your_file.xlsx', 'tabname', 'x_series_row_or_col', 'cell'))
	~	
	~		|

age_values[age]=
	1,2,3,4,5,6,7,8,9,10
	~	
	~		|
age:
	age 1,age 2,age 3,age 4,age 5,age 6,age 7,age 8,age 9,age 10
	~	
	~		|

I hope this can help you :)

[18811184907]

Hi @enekomartinmartinez
Thank you for your reply. I have made some progress.
In addition, I also found a problem. I made a modification in line 1291 of "vensim2py.py". Otherwise, an error will be reported when reading the “\”.
:

line 1291.txt

[18811184907]

Hi @enekomartinmartinez
I have another question. Will the next version add VECTOR ELM MAP() to the builder? Looking forward to your reply. Thank you.

[enekomartinmartinez]

Hi @18811184907
Thank you very much for notifying and correcting the bug :)
In order to implement the fix on PySD we have two options:

1. You can download the latest source code from git and open a pull request from a fork with the corrected version. In this case, I would ask you to add some tests as well (you can provide a small test model reproducing the bug opening a PR in test_models repo and adding the test to tests/integration_tests_vensim_pathway.py, it is also recommendable that you add a test in tests/unit_tests_vensim2py.py).
2. If you prefer it, you can provide me a small model example and I will create all the necessary tests and update PySD.

About VECTOR ELM MAP, I am not currently working on it. I give preference to the functions I need for the project I am working on, some of the functions I will add in the future have been already tracked in the issues section. In any case, I encourage you to develop this function, I can help you if you need it.

Thank you

[18811184907]

Thank you very much for sharing！ ------------------ 原始邮件 ------------------ 发件人: "JamesPHoughton/pysd" ***@***.***>; 发送时间: 2022年5月23日(星期一) 下午4:12 ***@***.***>; ***@***.******@***.***>; 主题: Re: [JamesPHoughton/pysd] Questions about subscript (Vensim function) (#296) Closed #296 as completed via #312. — Reply to this email directly, view it on GitHub, or unsubscribe. You are receiving this because you were mentioned.Message ID: ***@***.***>

[enekomartinmartinez]

You're welcome :)
Note that the PR only solves the first code you sent (running lookups with subscript variables and using subscripts as parameters).
The function VECTOR ELM MAP has not been included. I will open a new issue for that.