Python - 将CSV文件转换为JSON
我需要把一个csv文件转换成一个层级的JSON对象（最好是用Python）。我原以为我下面的这个脚本可以正确地转换成JSON，但我用来处理这些JSON数据的JavaScript库（D3.js）却无法正常工作。
这个csv文件的内容是这样的：
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，它可以递归地构建层级数组：
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()
目前我得到的结果大概是这样的：
{"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}]}]}
我觉得这可能在技术上符合JSON的规范，但我尝试用来处理这些JSON数据的库（D3.js）似乎无法使用它。是不是因为元素的顺序不对（比如“children”元素在“name”元素之前）？还是说我做的某些事情更基础的问题？
（我想要匹配的文件结构可以在这里找到。）
4 个回答
0
D3要求JSON中的值也要用双引号包起来。比如说，"level": 3 应该写成 "level": "3"。不过，当你在D3中使用这些数据进行计算时，它又需要变成数字。所以在D3代码中，你可以用 +data.xxx.yyy.level 来把它转换成数字，而不是直接用 data.xxx.yyy.level。
0
在 JSON 中，元素的顺序并不重要。
不过，你生成的 JSON 是错误的。你给出的例子中，顶层并没有 "subject" 这个键。它只显示了 "name" => "flare"，还有一系列的子元素。你的脚本生成的 JSON 却有一个 "subject" 键。
不要使用
subject_dict = {'name':subject,'type':'subject','children':branch_list}
试试
subject_dict = {'name':subject,'children':branch_list}
我对 D3.js 不太了解，所以不能确定它是否需要一个完全按照特定结构的对象。
小提示：一个检查 JSON 对象结构的好工具是 http://jsoneditor.appspot.com。只需把你的字符串粘贴进去，然后点击“Go to Treeview”。这样可以很轻松地帮助你找到你现有的和你想要的之间的差异。
6
这样做不行吗？
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