有没有办法不使用 Ansible 在 Jinja2 模板中格式化数字？

Question

Jinja2 seems to be shortening number when used in template with Ansible, I have this in: role/x/vars/main.yml: var_a: 0.010101010101010101

In role/x/templates/a.txt.j2: my_var_a={{ var_a }}

After running it, I get the number in a.txt shortened by two(missing 01 at the end): my_var_a=0.0101010101010101

Is there a way not to format it?

Answer 1

This is not a problem of Jinja but of the representation of floating point numbers in Python (and C).

I tried this in python:

>>> var_a= 0.010101010101010101
>>> print(var_a)
0.0101010101010101

So indeed the number is truncated. I advise you to read this explanation about floating point arithmetic .

Another example that shows the limitations:

>>> 0.1 + 0.2
0.30000000000000004