python dictionary with list values to numpy array

Question

Trying to convert a python dict that has:

nteger keys
length 4 integer lists as values

{38.0: [139.0, 1.8, 36.0, 18.2], etc}

into a numpy array, for analysis with sci-kit learn bayesian ridge regression.

define "convert" - what is the result supposed to look like? — timgeb
– timgeb, Commented Dec 13, 2015 at 15:48
What sort of array? Do you want an array with n rows and 5 columns, n rows and 4 columns, etc.? should the array just be rows of the lists in the dictionary or something else? — forkrul
– forkrul, Commented Dec 13, 2015 at 15:48

piman314 · Accepted Answer · 2015-12-14 15:35:31Z

1

Assuming you mean what I think you mean this is a simple way to do it (it's a bit shorter to use append but for large arrays always preallocate using numpy).

    myDict = {38.0: [139.0, 1.8, 36.0, 18.2], 39.0: [139.0, 1.8, 36.0, 18.2]}
    y = np.zeros(len(myDict))
    X = np.zeros((len(myDict), 4))
    i = 0
    for key, values in myDict.iteritems():
        y[i] = key
        X[i, :] = values
        i += 1

answered Dec 14, 2015 at 15:35

piman314

5,35526 silver badges36 bronze badges

Sign up to request clarification or add additional context in comments.

Collectives™ on Stack Overflow

python dictionary with list values to numpy array

1 Answer 1

Comments

Your Answer

Hot Network Questions

Collectives™ on Stack Overflow

1 Answer 1

Comments

Your Answer

Sign up or log in

Post as a guest

Related