What does the function name `ravel` stand for in `NumPy`?-CodePudding

What does ravel stand for in NumPy?

Sometimes, it is a bit harder to remember a function name that the name has nothing to do with its description.

CodePudding user response：

The dictionary meaning for ravel is

to become unwoven, untwisted, or unwound

We tend to use unravel in same way

to separate or undo the texture of : UNRAVEL

https://www.merriam-webster.com/dictionary/ravel

In numpy flatten does the same thing, except it always makes a copy. ravel is more like reshape(-1), returning a view where possible

It's use for computational arrays may trace back to apl in the 1960s.

https://aplwiki.com/wiki/Ravel.

CodePudding user response：

ravel means the same as unravel - to become unwoven, untwisted, or unwound

As for numpy ravel - a 1-D array, containing the elements of the input, is returned. So if you provide a 2D array to ravel, it will be unwoven, untwisted or unwound, to become a 1D array.

x = np.array([[1, 2, 3], 
              [4, 5, 6]])
np.ravel(x)

OUTPUT:
array([1, 2, 3, 4, 5, 6])