AI engineering glossary · Linear algebra
What is einstein summation?
Einstein summation (also called einsum): A compact notation that describes tensor products, contractions and transposes by naming each axis with a letter and summing over any letter that repeats. Array libraries offer it through an einsum function.
Einstein summation: an example
np.einsum('ij,jk->ik', A, B) performs ordinary matrix multiplication of A and B.
Related terms
More Linear algebra terms
- Frobenius norm
- Full rank
- Gaussian elimination
- Gram matrix
- Gram-Schmidt process
- Hadamard product
- Homogeneous coordinates
- Hyperplane
Where you learn it
Einstein summation is part of the AI Engineering Program, which teaches it with notes, a hands-on lab and an exam. The first lesson is free.