您可以使用csv2libsvm.py将csv转换为libsvm data

python csv2libsvm.py iris.csv libsvm.data 4 True

其中，4表示target index，True表示csv具有报头。
最后，您可以将libsvm.data作为

0 1:5.1 2:3.5 3:1.4 4:0.2
0 1:4.9 2:3.0 3:1.4 4:0.2
0 1:4.7 2:3.2 3:1.3 4:0.2
0 1:4.6 2:3.1 3:1.5 4:0.2
...

从iris.csv

150,4,setosa,versicolor,virginica
5.1,3.5,1.4,0.2,0
4.9,3.0,1.4,0.2,0
4.7,3.2,1.3,0.2,0
4.6,3.1,1.5,0.2,0
...

csv2libsvm.py不支持Python3，也不支持标签目标（字符串目标），我稍微修改了一下。现在，它应该可以与Python3以及标签目标一起工作。我对Python非常陌生，所以我的代码可能没有遵循最佳实践，但我希望它足够好，可以帮助到别人。

#!/usr/bin/env python

"""
Convert CSV file to libsvm format. Works only with numeric variables.
Put -1 as label index (argv[3]) if there are no labels in your file.
Expecting no headers. If present, headers can be skipped with argv[4] == 1.

"""

import sys
import csv
import operator
from collections import defaultdict

def construct_line(label, line, labels_dict):
    new_line = []
    if label.isnumeric():
        if float(label) == 0.0:
            label = "0"
    else:
        if label in labels_dict:
            new_line.append(labels_dict.get(label))
        else:
            label_id = str(len(labels_dict))
            labels_dict[label] = label_id
            new_line.append(label_id)

    for i, item in enumerate(line):
        if item == '' or float(item) == 0.0:
            continue
        elif item=='NaN':
            item="0.0"
        new_item = "%s:%s" % (i + 1, item)
        new_line.append(new_item)
    new_line = " ".join(new_line)
    new_line += "\n"
    return new_line

# ---

input_file = sys.argv[1]
try:
    output_file = sys.argv[2]
except IndexError:
    output_file = input_file+".out"

try:
    label_index = int( sys.argv[3] )
except IndexError:
    label_index = 0

try:
    skip_headers = sys.argv[4]
except IndexError:
    skip_headers = 0

i = open(input_file, 'rt')
o = open(output_file, 'wb')

reader = csv.reader(i)

if skip_headers:
    headers = reader.__next__()

labels_dict = {}
for line in reader:
    if label_index == -1:
        label = '1'
    else:
        label = line.pop(label_index)

    new_line = construct_line(label, line, labels_dict)
    o.write(new_line.encode('utf-8'))