Glossary · Phase 2 · Math, when you need it
Summation
Adding up a list of values, written with the Greek letter Σ: Σ xᵢ means add every xᵢ. In code it's a loop with a running total, or sum().
Try it now
A phrasebook in three groups: symbols that loop over many values, symbols that mark a special number, and symbols that compare.
Learn it properly
Reading math notation as code · Σ, subscripts, hats and bars, translated into Python you can run and test. About 25 minutes.
Other terms from the same lesson
- argmax: The input that makes a value biggest, rather than the biggest value itself. The argmax of a classifier's scores is the winning class.
- subscript: A small letter or number written low after a name to mark a position: xᵢ is the i-th x, written x[i] in Python.
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