Introduction to Importing Data in Python
Hugo Bowne-Anderson
Data Scientist at DataCamp
import numpy as np
filename = 'MNIST.txt'
data = np.loadtxt(filename, delimiter=',')
data
[[ 0. 0. 0. 0. 0.]
[ 86. 250. 254. 254. 254.]
[ 0. 0. 0. 9. 254.]
...,
[ 0. 0. 0. 0. 0.]
[ 0. 0. 0. 0. 0.]
[ 0. 0. 0. 0. 0.]]
import numpy as np
filename = 'MNIST_header.txt'
data = np.loadtxt(filename, delimiter=',', skiprows=1)
print(data)
[[ 0. 0. 0. 0. 0.]
[ 86. 250. 254. 254. 254.]
[ 0. 0. 0. 9. 254.]
...,
[ 0. 0. 0. 0. 0.]
[ 0. 0. 0. 0. 0.]
[ 0. 0. 0. 0. 0.]]
skiprows
: how many rows (not indices) you wish to skipimport numpy as np
filename = 'MNIST_header.txt'
data = np.loadtxt(filename, delimiter=',', skiprows=1, usecols=[0, 2])
print(data)
[[ 0. 0.]
[ 86. 254.]
[ 0. 0.]
...,
[ 0. 0.]
[ 0. 0.]
[ 0. 0.]]
usecols
: list of the indices of the columns you wish to keepdata = np.loadtxt(filename, delimiter=',', dtype=str)
titanic.csv
Name Sex Cabin Fare
Braund, Mr. Owen Harris male NaN 7.3
Cumings, Mrs. John Bradley female C85 71.3
Heikkinen, Miss. Laina female NaN 8.0
Futrelle, Mrs. Jacques Heath female C123 53.1
Allen, Mr. William Henry male NaN 8.05
titanic.csv
Name Sex Cabin Fare
Braund, Mr. Owen Harris male NaN 7.3
Cumings, Mrs. John Bradley female C85 71.3
Heikkinen, Miss. Laina female NaN 8.0
Futrelle, Mrs. Jacques Heath female C123 53.1
Allen, Mr. William Henry male NaN 8.05
^ ^
strings floats
Introduction to Importing Data in Python