Python - 将 csv 文件转换为 JSON
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【中文标题】Python - 将 csv 文件转换为 JSON【英文标题】：Python - convert csv file to JSON 【发布时间】：2011-11-23 03:00:49 【问题描述】：我需要将 csv 文件转换为分层 JSON 对象（最好使用 Python）。我认为我拥有的脚本（如下）可以正确地转换为 JSON，但是我将 JSON 数据提供给 (D3.js) 的 javascript 库无法使用它。
csv 文件如下所示：
subject,branch,book,chapter,Encode ID,Level 1,Level 2,Level 3,Level 4
MAT,TRI,CK-12 Trigonometry - Second Edition,Right Triangles and an Introduction to Trigonometry,MAT.TRI.000,Right Triangles and an Introduction to Trigonometry,,,
MAT,TRI,CK-12 Trigonometry - Second Edition,Right Triangles and an Introduction to Trigonometry,MAT.TRI.004,,The Pythagorean Theorem,,
MAT,TRI,CK-12 Trigonometry - Second Edition,Right Triangles and an Introduction to Trigonometry,MAT.TRI.005,,,The Pythagorean Theorem,
MAT,TRI,CK-12 Trigonometry - Second Edition,Right Triangles and an Introduction to Trigonometry,MAT.TRI.006,,,Pythagorean Triples,
MAT,TRI,CK-12 Trigonometry - Second Edition,Right Triangles and an Introduction to Trigonometry,MAT.TRI.007,,,Converse of the Pythagorean Theorem,
MAT,TRI,CK-12 Trigonometry - Second Edition,Right Triangles and an Introduction to Trigonometry,MAT.TRI.008,,,The Distance Formula,
MAT,TRI,CK-12 Trigonometry - Second Edition,Right Triangles and an Introduction to Trigonometry,MAT.TRI.009,,Special Right Triangles,,
现在，我有以下代码递归构建分层数组：
import csv
import json
import random
random.seed()
# open up the csv file
f = open('/path/to/file','rU')
c = csv.DictReader(f)
# lists for keeping track of what subjects and branches I've already iterated over
subject_list = []
branch_list = []
lev1_list = []
lev2_list = []
lev3_list = []
lev4_list = []
# iterate through file
i = 0
for row in c:
if i == 0:
subject = row['subject']
branch = row['branch']
if len(row['Level 1']) > 0:
lev1 = row['Level 1']
else:
lev2 = None
if len(row['Level 2']) > 0:
lev2 = row['Level 2']
else:
lev2 = None
if len(row['Level 3']) > 0:
lev3 = row['Level 3']
else:
lev3 = None
else:
if row['subject'] != subject:
# add all branches to this subject
subject_list.append('name':subject,'type':'subject','children':branch_list)
# set current subject
subject = row['subject']
if row['branch'] != branch:
# add all concepts to this branch
branch_list.append('name':branch,'type':'branch','children':lev1_list)
# empty lev1_list
lev1_list = []
# set new branch
branch = row['branch']
if len(row['Level 1']) > 0 and row['Level 1'] != lev1:
# print lev1
# add all level 2 concepts to this level 1
lev1_list.append('name':lev1,'type':'concept','level':1,'children':lev2_list)
#print lev1
#empty lev2_list
lev2_list = []
#lev1_list.append(row['Level 1'])
lev1 = row['Level 1']
if len(row['Level 2']) > 0 and row['Level 2'] != lev3:
#print lev2
#print lev3_list
# add all level 3 concepts to this level 2
if lev2 is not None:
lev2_list.append('name':lev2,'type':'concept','level':2,'children':lev3_list)
# empty lev3_list
lev3_list = []
# lev2_list.append(row['Level 2'])
lev2 = row['Level 2']
if len(row['Level 3']) > 0 and row['Level 3'] != lev3:
# print lev3
# add all level 4 concepts to this level 4
# lev3_list.append('name':lev3,'type':'concept','level':3)
# empty level 4 concepts
# lev4_list = []
# add new level 3
if lev3 is not None:
lev3_list.append('name':lev3,'type':'concept','level':3,'size':random.randint(1,100))
lev3 = row['Level 3']
#if row['Level 4'] is not None and row['Level 4'] is not lev4:
# lev4_list.append('name':lev4,'type':'concept','level':4)
# lev4 = row['Level 4']
i += 1
f.close()
branch_list.append('name':branch,'type':'branch','children':lev1_list)
#subject_list.append('name':subject,'type':'subject','children':branch_list)
subject_dict = 'name':subject,'type':'subject','children':branch_list
#json_list= json.dumps(subject_list)
json_list = json.dumps(subject_dict)
f = open('/Users/thaymore/Sites/d3/data/trig_map.json','wb')
f.write(json_list)
f.close()
我现在得到的是这样的：
"type": "subject", "name": "MAT", "children": ["type": "branch", "name": "TRI", "children": ["children": ["children": ["size": 40, "type": "concept", "name": "The Pythagorean Theorem", "level": 3, "size": 19, "type": "concept", "name": "Pythagorean Triples", "level": 3, "size": 68, "type": "concept", "name": "Converse of the Pythagorean Theorem", "level": 3], "type": "concept", "name": "The Pythagorean Theorem", "level": 2, "children": ["size": 28, "type": "concept", "name": "The Distance Formula", "level": 3, "size": 49, "type": "concept", "name": "Special Right Triangle #1: Isosceles Right Triangle", "level": 3, "size": 33, "type": "concept", "name": "Special Right Triangle #2: 30-60-90 Triangle", "level": 3], "type": "concept", "name": "Special Right Triangles", "level": 2, "children": ["size": 18, "type": "concept", "name": "Using Special Right Triangle Ratios", "level": 3, "size": 49, "type": "concept", "name": "The Sine, Cosine, and Tangent Functions", "level": 3], "type": "concept", "name": "Basic Trigonometric Functions", "level": 2, "children": ["size": 100, "type": "concept", "name": "Secant, Cosecant, and Cotangent Functions", "level": 3, "size": 73, "type": "concept", "name": "Solving Right Triangles", "level": 3, "size": 93, "type": "concept", "name": "Inverse Trigonometric Functions", "level": 3, "size": 88, "type": "concept", "name": "Finding the Area of a Triangle", "level": 3, "size": 6, "type": "concept", "name": "Angles of Elevation and Depression", "level": 3, "size": 3, "type": "concept", "name": "Right Triangles and Bearings", "level": 3], "type": "concept", "name": "Solving Right Triangles", "level": 2, "children": ["size": 68, "type": "concept", "name": "Other Applications of Right Triangles", "level": 3, "size": 92, "type": "concept", "name": "Angles of Rotation in Standard Position", "level": 3], "type": "concept", "name": "Measuring Rotation", "level": 2, "children": ["size": 14, "type": "concept", "name": "Coterminal Angles", "level": 3, "size": 68, "type": "concept", "name": "Trigonometric Functions of Angles in Standard Position", "level": 3], "type": "concept", "name": "Applying Trig Functions to Angles of Rotation", "level": 2, "children": ["size": 61, "type": "concept", "name": "The Unit Circle", "level": 3, "size": 95, "type": "concept", "name": "Reference Angles and Angles in the Unit Circle", "level": 3, "size": 11, "type": "concept", "name": "Trigonometric Functions of Negative Angles", "level": 3, "size": 45, "type": "concept", "name": "Trigonometric Functions of Angles Greater than 360 Degrees", "level": 3], "type": "concept", "name": "Trigonometric Functions of Any Angle", "level": 2], "type": "concept", "name": "Right Triangles and an Introduction to Trigonometry", "level": 1, "children": ["children": ["size": 20, "type": "concept", "name": "Using a Calculator to Find Values", "level": 3, "size": 25, "type": "concept", "name": "Reciprocal identities", "level": 3, "size": 40, "type": "concept", "name": "Domain, Range, and Signs of Trig Functions", "level": 3, "size": 97, "type": "concept", "name": "Quotient Identities", "level": 3, "size": 18, "type": "concept", "name": "Cofunction Identities and Reflection", "level": 3], "type": "concept", "name": "Relating Trigonometric Functions", "level": 2, "children": ["size": 35, "type": "concept", "name": "Pythagorean Identities", "level": 3, "size": 95, "type": "concept", "name": "Understanding Radian Measure", "level": 3, "size": 30, "type": "concept", "name": "Critial Angles in Radians", "level": 3, "size": 16, "type": "concept", "name": "Converting Any Degree to Radians", "level": 3, "size": 25, "type": "concept", "name": "The Six Trig Functions and Radians", "level": 3], "type": "concept", "name": "Radian Measure", "level": 2, "children": ["size": 19, "type": "concept", "name": "Check the Mode", "level": 3, "size": 63, "type": "concept", "name": "Rotations", "level": 3, "size": 33, "type": "concept", "name": "Length of Arc", "level": 3, "size": 54, "type": "concept", "name": "Area of a Sector", "level": 3, "size": 6, "type": "concept", "name": "Length of a Chord", "level": 3], "type": "concept", "name": "Applications of Radian Measure", "level": 2, "children": ["size": 71, "type": "concept", "name": "Angular Velocity", "level": 3, "size": 16, "type": "concept", "name": "The Sine Graph", "level": 3, "size": 65, "type": "concept", "name": "The Cosine Graph", "level": 3, "size": 32, "type": "concept", "name": "The Tangent Graph", "level": 3, "size": 93, "type": "concept", "name": "The Three Reciprocal Functions", "level": 3, "size": 30, "type": "concept", "name": "Cotangent", "level": 3, "size": 4, "type": "concept", "name": "Cosecant", "level": 3], "type": "concept", "name": "Circular Functions of Real Numbers", "level": 2, "children": ["size": 100, "type": "concept", "name": "Secant", "level": 3, "size": 40, "type": "concept", "name": "Vertical Translations", "level": 3], "type": "concept", "name": "Translating Sine and Cosine Functions", "level": 2, "children": ["size": 58, "type": "concept", "name": "Horizontal Translations or Phase Shifts", "level": 3, "size": 76, "type": "concept", "name": "Amplitude", "level": 3, "size": 91, "type": "concept", "name": "Period and Frequency", "level": 3], "type": "concept", "name": "Amplitude, Period and Frequency", "level": 2, "children": ["size": 78, "type": "concept", "name": "Combining Amplitude and Period", "level": 3, "size": 12, "type": "concept", "name": "The Generalized Equations", "level": 3, "size": 22, "type": "concept", "name": "Drawing Sketches/Identifying Transformations from the Equation", "level": 3], "type": "concept", "name": "General Sinusoidal Graphs", "level": 2], "type": "concept", "name": "Graphing Trigonometric Functions - 2nd edition", "level": 1, "children": ["children": ["size": 81, "type": "concept", "name": "Writing the Equation from a Sketch", "level": 3, "size": 60, "type": "concept", "name": "Tangent and Cotangent", "level": 3, "size": 27, "type": "concept", "name": "Secant and Cosecant", "level": 3], "type": "concept", "name": "Graphing Tangent, Cotangent, Secant, and Cosecant", "level": 2, "children": ["size": 62, "type": "concept", "name": "Graphing Calculator Note", "level": 3, "size": 20, "type": "concept", "name": "Quotient Identity", "level": 3, "size": 15, "type": "concept", "name": "Reciprocal Identities", "level": 3, "size": 28, "type": "concept", "name": "Pythagorean Identity", "level": 3, "size": 28, "type": "concept", "name": "Even and Odd Identities", "level": 3], "type": "concept", "name": "Fundamental Identities", "level": 2, "children": ["size": 24, "type": "concept", "name": "Cofunction Identities", "level": 3, "size": 91, "type": "concept", "name": "Working with Trigonometric Identities", "level": 3], "type": "concept", "name": "Proving Identities", "level": 2, "children": ["size": 59, "type": "concept", "name": "Technology Note", "level": 3, "size": 26, "type": "concept", "name": "Simplifying Trigonometric Expressions", "level": 3, "size": 94, "type": "concept", "name": "Solving Trigonometric Equations", "level": 3, "size": 49, "type": "concept", "name": "Solving Trigonometric Equations Using Factoring", "level": 3], "type": "concept", "name": "Solving Trigonometric Equations", "level": 2, "children": ["size": 25, "type": "concept", "name": "Solving Trigonometric Equations Using the Quadratic Formula", "level": 3, "size": 11, "type": "concept", "name": "Sum and Difference Formulas: cosine", "level": 3, "size": 30, "type": "concept", "name": "Using the Sum and Difference Identities of cosine", "level": 3, "size": 75, "type": "concept", "name": "Sum and Difference Identities: sine", "level": 3, "size": 94, "type": "concept", "name": "Sum and Difference Identities: Tangent", "level": 3, "size": 22, "type": "concept", "name": "Using the Sum and Difference Identities to Verify Other Identities", "level": 3], "type": "concept", "name": "Sum and Difference Identities", "level": 2, "children": ["size": 15, "type": "concept", "name": "Solving Equations with the Sum and Difference Formulas", "level": 3, "size": 88, "type": "concept", "name": "Deriving the Double Angle Identities", "level": 3, "size": 42, "type": "concept", "name": "Applying the Double Angle Identities", "level": 3], "type": "concept", "name": "Double Angle Identities", "level": 2, "children": ["size": 13, "type": "concept", "name": "Solving Equations with Double Angle Identities", "level": 3, "size": 36, "type": "concept", "name": "Deriving the Half Angle Formulas", "level": 3], "type": "concept", "name": "Half-Angle Identities", "level": 2], "type": "concept", "name": "Trigonometric Identities and Equations - 2nd edition", "level": 1, "children": ["children": ["size": 100, "type": "concept", "name": "Solving Trigonometric Equations Using Half Angle Formulas", "level": 3, "size": 93, "type": "concept", "name": "Sum to Product Formulas for Sine and Cosine", "level": 3, "size": 71, "type": "concept", "name": "Product to Sum Formulas for Sine and Cosine", "level": 3, "size": 53, "type": "concept", "name": "Solving Equations with Product and Sum Formulas", "level": 3, "size": 45, "type": "concept", "name": "Triple-Angle Formulas and Beyond", "level": 3, "size": 18, "type": "concept", "name": "Linear Combinations", "level": 3], "type": "concept", "name": "Products, Sums, Linear Combinations, and Applications", "level": 2, "children": ["size": 73, "type": "concept", "name": "Applications & Technology", "level": 3, "size": 54, "type": "concept", "name": "Defining the Inverse of the Trigonometric Ratios", "level": 3, "size": 15, "type": "concept", "name": "Exact Values for Inverse Sine, Cosine, and Tangent", "level": 3], "type": "concept", "name": "Basic Inverse Trigonometric Functions", "level": 2, "children": ["size": 1, "type": "concept", "name": "Finding Inverses Algebraically", "level": 3, "size": 93, "type": "concept", "name": "Finding the Inverse by Mapping", "level": 3], "type": "concept", "name": "Graphing Inverse Trigonometric Functions", "level": 2, "children": ["size": 79, "type": "concept", "name": "Finding the Inverse of the Trigonometric Functions", "level": 3, "size": 29, "type": "concept", "name": "Composing Trig Functions and their Inverses", "level": 3, "size": 19, "type": "concept", "name": "Composing Trigonometric Functions", "level": 3, "size": 53, "type": "concept", "name": "Inverse Reciprocal Functions", "level": 3, "size": 28, "type": "concept", "name": "Composing Inverse Reciprocal Trig Functions", "level": 3], "type": "concept", "name": "Inverse Trigonometric Properties", "level": 2], "type": "concept", "name": "Inverse Trigonometric Functions - 2nd edition", "level": 1, "children": ["children": [], "type": "concept", "name": "Applications & Models", "level": 2, "children": ["size": 42, "type": "concept", "name": "Trigonometry in Terms of Algebra", "level": 3, "size": 38, "type": "concept", "name": "Derive the Law of Cosines", "level": 3, "size": 82, "type": "concept", "name": "Case #1: Finding the Side of an Oblique Triangle", "level": 3, "size": 68, "type": "concept", "name": "Case #2: Finding any Angle of a Triangle", "level": 3], "type": "concept", "name": "The Law of Cosines", "level": 2, "children": ["size": 20, "type": "concept", "name": "Identify Accurate Drawings of General Triangles", "level": 3, "size": 90, "type": "concept", "name": "Find the Area Using Three Sides: Heron\u2019s Formula", "level": 3, "size": 7, "type": "concept", "name": "Heron\u2019s Formula:", "level": 3], "type": "concept", "name": "Area of a Triangle", "level": 2, "children": ["size": 21, "type": "concept", "name": "Finding a Part of the Triangle, Given the Area", "level": 3, "size": 58, "type": "concept", "name": "Deriving the Law of Sines", "level": 3, "size": 15, "type": "concept", "name": "AAS (Angle-Angle-Side)", "level": 3, "size": 41, "type": "concept", "name": "ASA (Angle-Side-Angle)", "level": 3], "type": "concept", "name": "The Law of Sines", "level": 2, "children": ["size": 87, "type": "concept", "name": "Solving Triangles", "level": 3, "size": 31, "type": "concept", "name": "Possible Triangles with SSA", "level": 3, "size": 45, "type": "concept", "name": "Using the Law of Sines", "level": 3], "type": "concept", "name": "The Ambiguous Case", "level": 2, "children": ["size": 40, "type": "concept", "name": "Using the Law of Cosines", "level": 3, "size": 2, "type": "concept", "name": "Summary of Triangle Techniques", "level": 3, "size": 18, "type": "concept", "name": "Using the Law of Cosines", "level": 3], "type": "concept", "name": "General Solutions of Triangles", "level": 2, "children": ["size": 42, "type": "concept", "name": "Using the Law of Sines", "level": 3, "size": 6, "type": "concept", "name": "Directed Line Segments, Equal Vectors, and Absolute Value", "level": 3, "size": 60, "type": "concept", "name": "Vector Addition", "level": 3, "size": 76, "type": "concept", "name": "Vector Subtraction", "level": 3], "type": "concept", "name": "Vectors", "level": 2], "type": "concept", "name": "Triangles and Vectors", "level": 1]]
我认为这在技术上可能符合 JSON 规范，但我尝试将 JSON 数据提供给 (D3.js) 的库似乎无法使用它。是不是因为元素的顺序不正常（即“children”元素在“name”元素之前）？是不是我在做一些更基本的事情？
（我要匹配其结构的文件位于here。）
【问题讨论】：
将所有dicts 切换为OrderedDicts 来检查是否是订单并反馈。
你说的“似乎无法用它做任何事情”是什么意思？甚至无法解析它（例如，示例末尾的额外逗号可能只是导致解析错误），或者更具体的东西？
@agf 运行 Python 2.6 -- OrderedDict 在该版本中可用吗？
@ZachSnow 额外的逗号只是因为我截断了数据。 D3.js 库应该能够将 JSON 对象转换为分层节点布局，这与我上面链接到的默认 JSON 文件配合得很好。但是，对于我的 JSON 数据，它什么也不做——就好像它无法处理数据，或者返回一个“未定义”节点。
为了帮助我们验证您的返回输出是否正确，您能否提供完整的 JSON 输出？很难确定你在“等等”之前从哪里停下来。
【参考方案1】：
这不行吗？
import json
f = open('path/to/file','r')
arr=[]
headers = []
for header in f.readline().split(','):
headers.append(header)
for line in f.readlines():
lineItems =
for i,item in enumerate(line.split(',')):
lineItems[headers[i]] = item
arr.append(lineItems)
f.close()
jsonText = json.dumps(arr)
print jsonText
【讨论】：
【参考方案2】：元素的顺序对于 json 并不重要。
但是，您生成的 json 是错误的。您尝试匹配的示例在顶层没有“主题”键。它只显示“name”=>“flare”和一个孩子列表。您的脚本正在生成带有“主题”键的 json。
代替
subject_dict = 'name':subject,'type':'subject','children':branch_list
试试
subject_dict = 'name':subject,'children':branch_list
我不了解 D3.js，所以我不能说它是否需要一个遵循一个确切结构的对象。
提示：检查 json 对象结构的一个好工具是http://jsoneditor.appspot.com。只需将您的字符串粘贴到那里，然后单击“转到树视图”。它会帮助你很容易地发现你所拥有的和你想要的之间的差异。
【讨论】：
【参考方案3】：D3 期望 JSON 中的值也包含在双引号中。所以例如“级别”：3 应该是“级别”：“3”。当您在 D3 中使用此数据进行计算时，它需要再次成为一个数字，因此您可以在使用它的地方使用 +data.xxx.yyy.level 而不是 d3 代码中的 data.xxx.yyy.level 转把它变成一个数字。
【讨论】：
【参考方案4】：import csv
import json
file1 = csv.DictReader(open('filename.csv', 'r'))
output =[]
for each in complent:
row =
row['Id'] = each['Id']
row['Name'] = each['Name']
row['Address'] = each['Address']
row['Mobile'] = each['Mobile']
row['LandLine'] = each['LandLine']
row['Email'] = each['Email']
output.append(row)
json.dump(output,open('new_file.json','w'),indent=4,sort_keys=False)
【讨论】：
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