mat2json, python读取mat成字典, 保存json

python程序, 实现matlab的.mat格式转化为dict / json .

• 第一个参数mat_path表明须要转化的mat路径;
• 第二个参数, 若是须要把字典序列化成json, 添加这一参数, 表明json存放位置;
• 返回值: 转化好的字典

import os
import json
import scipy.io as spio
import pandas as pd

def loadmat(filename):
    '''
    this function should be called instead of direct spio.loadmat
    as it cures the problem of not properly recovering python dictionaries
    from mat files. It calls the function check keys to cure all entries
    which are still mat-objects
    '''
    data = spio.loadmat(filename, struct_as_record=False, squeeze_me=True)
    return _check_keys(data)

def _check_keys(dict):
    '''
    checks if entries in dictionary are mat-objects. If yes
    todict is called to change them to nested dictionaries
    '''
    for key in dict:
        if isinstance(dict[key], spio.matlab.mio5_params.mat_struct):
            dict[key] = _todict(dict[key])
    return dict

def _todict(matobj):
    '''
    A recursive function which constructs from matobjects nested dictionaries
    '''
    dict = {}
    for strg in matobj._fieldnames:
        elem = matobj.__dict__[strg]
        if isinstance(elem, spio.matlab.mio5_params.mat_struct):
            dict[strg] = _todict(elem)
        else:
            dict[strg] = elem
    return dict

def mat2json(mat_path=None, filepath = None):
    """
    Converts .mat file to .json and writes new file
    Parameters
    ----------
    mat_path: Str
        path/filename .mat存放路径
    filepath: Str
        若是须要保存成json, 添加这一路径. 不然不保存
    Returns
        返回转化的字典
    -------
    None
    Examples
    --------
    >>> mat2json(blah blah)
    """

    matlabFile = loadmat(mat_path)
    #pop all those dumb fields that don't let you jsonize file
    matlabFile.pop('__header__')
    matlabFile.pop('__version__')
    matlabFile.pop('__globals__')
    #jsonize the file - orientation is 'index'
    matlabFile = pd.Series(matlabFile).to_json()

    if filepath:
        json_path = os.path.splitext(os.path.split(mat_path)[1])[0] + '.json'
        with open(json_path, 'w') as f:
                f.write(matlabFile)
    return matlabFile

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更改自mat2json