  This paper introduces the first release of Pytearcat, a Python package
developed to compute tensor algebra operations in the context of theoretical
physics, for instance, in general relativity. Given that working with tensors
can become a complex task, people often rely on computational tools to perform
tensor calculations. We aim to build a tensor calculator based on Python, which
benefits from being free and easy to use. Pytearcat syntax resembles the usual
physics notation for tensor calculus, such as the Einstein notation for index
contraction. This version allows the user to perform many tensor operations,
including derivatives and series expansions, along with routines to obtain the
typical General Relativity tensors. A particular concern was put in the
execution times, leading to incorporate an alternative core for the symbolic
calculations, enabling to reach much faster execution times. The syntax and the
versatility of Pytearcat are the most important features of this package, where
the latter can be used to extend Pytearcat to other areas of theoretical
physics.
