# Variables with Janus

**URL:** <https://swi-prolog.discourse.group/t/variables-with-janus/7446>\
**Category:** Help!\
**Tags:** how-to\
**Created:** [May 13, 2024, 10:31am UTC](https://swi-prolog.discourse.group/t/variables-with-janus/7446 "2024-05-13T10:31:56Z")\
**Posts on this page:** 1\
**Showing post:** 1

<div class="post-metadata">

**Author:** ![Nema](https://avatars.discourse-cdn.com/v4/letter/n/97f17d/32.png) [@Nema](https://swi-prolog.discourse.group/u/Nema)\
**Post date:** [May 13, 2024, 10:31am UTC](https://swi-prolog.discourse.group/t/variables-with-janus/7446/1 "2024-05-13T10:31:56Z")

</div>

I’m using janus to call Prolog from Python code. I don’t understand why, if I write

```prolog

janus.consult("rules", """
    rule([1,1,0,0]).
    """)
answer1 = janus.query_once("rule([1,1,0,0])")
print(answer1)

```

output: {‘truth’: True}

which is correct, but if I use lists/tuple or numpy arrays as

```prolog
import numpy as np

line = np.array([1,1,0,0])

janus.consult("rules", """
    rule(line).
    """)

d = np.array([1,1,0,0])
answer1 = janus.query_once("rule(d)")
print(answer1)

```

output: {‘truth’: False}  
which is wrong.

How can I use variables in janus? What am I doing wrong?

Thank you for four time

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