解析CSV文件以转换为JSON格式文件

时间:2013-07-23 21:20:45

标签: javascript python scripting

我获得了以下从excel电子表格中提取的CSV文件。只是为了提供一些可能有帮助的背景信息,它讨论了AGI编号(将其视为蛋白质标识符),未修饰的那些蛋白质标识符的肽序列,然后修饰了对未修饰序列进行修饰的肽序列,索引/缺陷那些修饰,然后是重复肽的组合光谱计数。文本文件名为MASP.GlycoModReader.txt,信息格式如下:

AGI,UnMd Peptide (M) = x,Mod Peptide (oM) = Ox,Index/Indeces of Modification,counts,Combined 
Spectral count for repeated Peptides

AT1G56070.1,NMSVIAHVDHGKSTLTDSLVAAAGIIAQEVAGDVR,NoMSVIAHVDHGKSTLTDSLVAAAGIIAQEVAGDVR,2,17
AT1G56070.1,LYMEARPMEEGLAEAIDDGR,LYoMEARPoMEEGLAEAIDDGR,"3, 9",1
AT1G56070.1,EAMTPLSEFEDKL,EAoMTPLSEFEDKL,3,7
AT1G56070.1,LYMEARPMEEGLAEAIDDGR,LYoMEARPoMEEGLAEAIDDGR,"3, 9",2
AT1G56070.1,EGPLAEENMR,EGPLAEENoMR,9,2
AT1G56070.1,DLQDDFMGGAEIIK,DLQDDFoMGGAEIIK,7,1

解压缩上述内容后需要生成的输出文件格式如下:

AT1G56070.1,{"peptides": [{"sequence": "NMSVIAHVDHGKSTLTDSLVAAAGIIAQEVAGDVR", "mod_sequence":    
"NoMSVIAHVDHGKSTLTDSLVAAAGIIAQEVAGDVR" , "mod_indeces": 2, "spectral_count": 17}, {"sequence": 
"LYMEARPMEEGLAEAIDDGR" , "mod_sequence": "LYoMEARPoMEEGLAEAIDDGR", "mod_indeces": [3, 9], 
"spectral_count": 3}, {"sequence": "EAMTPLSEFEDKL" , "mod_sequence": "EAoMTPLSEFEDKL", 
"mod_indeces": [3,9], "spectral_count": 7}, {"sequence": "EGPLAEENMR", "mod_sequence": 
"EGPLAEENoMR", "mod_indeces": 9, "spectral_count": 2}, {"sequence": "DLQDDFMGGAEIIK", 
"mod_sequence": "DLQDDFoMGGAEIIK", "mod_indeces": [7], "spectral_count": 1}]}

我在下面提供了我的解决方案:如果有人用另一种语言有更好的解决方案,或者可以分析我的,并告诉我是否有更有效的方法来解决这个问题,请在下面评论。谢谢。

    #!/usr/bin/env node

    var fs = require('fs');
    var csv = require('csv');
    var data ="proteins.csv";

    /* Uses csv nodejs module to parse the proteins.csv file.
    * Parses the csv file row by row and updates the peptide_arr.
    * For new entries creates a peptide object, for similar entries it updates the
    * counts in the peptide object with the same AGI#.
    * Uses a peptide object to store protein ID AGI#, and the associated data.
    * Writes all formatted peptide objects to a txt file - output.txt.
    */

    // Tracks current row
    var x = 0;
    // An array of peptide objects stores the information from the csv file
    var peptide_arr = [];

    // csv module reads row by row from data 
    csv()
    .from(data)
    .to('debug.csv')
    .transform(function(row, index) {
        // For the first entry push a new peptide object with the AGI# (row[0]) 
        if(x == 0) {
        // cur is the current peptide read into row by csv module
        Peptide cur = new Peptide( row[0] );

        // Add the assoicated data from row (1-5) to cur
        cur.data.peptides.push({
            "sequence" : row[1];
            "mod_sequence" : row[2];
            if(row[5]){
            "mod_indeces" : "[" + row[3] + ", " + row[4] + "]";
            "spectral_count" : row[5];  
            } else {
            "mod_indeces" : row[3];
            "spectral_count" : row[4];  
            }
        });

        // Add the current peptide to the array
        peptide_arr.push(cur);
        }

        // Move to the next row
        x++;
    });

    // Loop through peptide_arr and append output with each peptide's AGI# and its data
    String output = "";
    for(var peptide in peptide_arr) 
    {
        output = output + peptide.toString()
    }
    // Write the output to output.txt
    fs.writeFile("output.txt", output);

    /* Peptide Object :
     *  - id:AGI#
     *  - data: JSON Array associated
     */
    function Peptide(id) // this is the actual function that does the ID retrieving and data 
                        // storage
{
    this.id = id;
    this.data = {
        peptides: []
    };
}

/* Peptide methods :
 *  - toJson : Returns the properly formatted string
 */
Peptide.prototype = {
    toString: function(){
        return this.id + "," + JSON.stringify(this.data, null, " ") + "/n"
    }
};

编辑说明:似乎当我运行此解决方案时,我发布了内存泄漏错误;它无限运行,而不产生任何实质,可读的输出。如果有人愿意协助评估为什么会这样,那就太好了。

1 个答案:

答案 0 :(得分:0)

你的版本有用吗?看起来你只创建了一个Peptide对象。另外,“if(row [5])”语句在做什么?在您的示例数据中,总共有5个元素。另外,mod_indeces总是应该是一个列表,对吗?因为在您的示例输出文件中,mod_indeces不是第一个肽中的列表。无论如何,这是我在python中提出的:

import csv
import json
data = {}
with open('proteins.csv','rb') as f:
    reader = csv.reader(f)
    for row in reader:
        name = row[0]
        sequence = row[1]
        mod_sequence = row[2]
        mod_indeces = map(int,row[3].split(', '))
        spectral_count = int(row[4])
        peptide = {'sequence':sequence,'mod_sequence':mod_sequence,
                   'mod_indeces':mod_indeces,'spectral_count':spectral_count}
        if name in data:
            data[name]['peptides'].append(peptide)
        else:
            data[name] = {'peptides':[peptide]}
    f.close()

f = open('output.txt','wb')
for protein in data:
    f.write(protein)
    f.write(',')
    f.write(json.dumps(data[protein]))
    f.write('\n')
f.close()

如果您在Windows上并希望以纯文本格式查看文件,则可能需要将'\ n'替换为'\ r \ n'或os.linesep。

如果你想跳过某些行(如果有标题或其他内容),你可以这样做:

import csv
import json
data = {}
rows_to_skip = 1
rows_read = 0
with open('proteins.csv','rb') as f:
    reader = csv.reader(f)
    for row in reader:
        if rows_read >= rows_to_skip:
            name = row[0]
            sequence = row[1]
            mod_sequence = row[2]
            mod_indeces = map(int,row[3].split(', '))
            spectral_count = int(row[4])
            peptide = {'sequence':sequence,'mod_sequence':mod_sequence,
                       'mod_indeces':mod_indeces,'spectral_count':spectral_count}
            if name in data:
                data[name]['peptides'].append(peptide)
            else:
                data[name] = {'peptides':[peptide]}
        rows_read += 1
    f.close()

f = open('output.txt','wb')
for protein in data:
    f.write(protein)
    f.write(',')
    f.write(json.dumps(data[protein]))
    f.write('\n')
f.close()

如果希望字典的键按特定顺序排列,则可以使用orderedDict而不是默认字典。只需用以下代码替换肽系列:

peptide = OrderedDict([('sequence',sequence),
                       ('mod_sequence',mod_sequence),
                       ('mod_indeces',mod_indeces),
                       ('spectral_count',spectral_count)])

现在订单已保留。也就是说,sequence之后是mod_sequence,后跟mod_indeces,后跟spectral_count。要更改顺序,只需更改OrderedDict中元素的顺序。

请注意,您还必须添加from collections import OrderedDict才能使用OrderedDict。