Read Matlab Data File into Python, Need to Export to CSV

please use hdf reader for matlab v7.3 files
read mat file python
read mat file python pandas
convert mat file to csv octave
convert mat file to csv online
transfer data from matlab to python
python read matlab fig file
read matlab cell array in python

I have read a Matlab file containing a large amount of arrays as a dataset into Python storing the Matlab Dictionary under the variable name mat using the command:

mat = loadmat('Sample Matlab Extract.mat')

Is there a way I can then use Python's write to csv functionality to save this Matlab dictionary variable I read into Python as a comma separated file?

with open('mycsvfile.csv','wb') as f:
   w = csv.writer(f)
   w.writerows(mat.items())
   f.close()

creates a CSV file with one column containing array names within the dictionary and then another column containing the first element of each corresponding array. Is there a way to utilize a command similar to this to obtain all corresponding elements within the arrays inside of the 'mat' dictionary variable?

The function scipy.io.loadmat generates a dictionary looking something like this:

{'__globals__': [],
 '__header__': 'MATLAB 5.0 MAT-file, Platform: MACI, Created on: Wed Sep 24 16:11:51 2014',
 '__version__': '1.0',
 'a': array([[1, 2, 3]], dtype=uint8),
 'b': array([[4, 5, 6]], dtype=uint8)}

It sounds like what you want to do is make a .csv file with the keys "a", "b", etc. as the column names and their corresponding arrays as data associated with each column. If so, I would recommend using pandas to make a nicely formatted dataset that can be exported to a .csv file. First, you need to clean out the commentary members of your dictionary (all the keys beginning with "__"). Then, you want to turn each item value in your dictionary into a pandas.Series object. The dictionary can then be turned into a pandas.DataFrame object, which can also be saved as a .csv file. Your code would look like this:

import scipy.io
import pandas as pd

mat = scipy.io.loadmat('matex.mat')
mat = {k:v for k, v in mat.items() if k[0] != '_'}
data = pd.DataFrame({k: pd.Series(v[0]) for k, v in mat.iteritems()})
data.to_csv("example.csv")

How to convert a .mat file into a .csv file?, I have a .mat file loaded in workspace. I want to Trouble reading number from file (row 1u, field 1u) ==> You cannot write a struct directly to an CSV file. Use "writematrix" to export matrix data as a CSV file instead. When writing matrix data to a file, you can specify the file type as part of the file name in the second argument of the function call: m = [234 2;671 5;735 1;264 2;346 7]

This is correct solution for converting any .mat file into .csv file. Try it

   import scipy.io
   import numpy as np
   data = scipy.io.loadmat("file.mat")

   for i in data:
        if '__' not in i and 'readme' not in i:
              np.savetxt(("file.csv"),data[i],delimiter=',')

.mat file not converting to .csv - MATLAB Answers, As I primarily work in Python, I would like to convert this to a csv file. I load the . mat file into As I have been reading online, since it is a struct, I need to specify which variables to convert to csv for it to export properly. However� Designed to work out of the box with Excel-generated CSV files, it is easily adapted to work with a variety of CSV formats. The csv library contains objects and other code to read, write, and process data from and to CSV files. Reading CSV Files With csv. Reading from a CSV file is done using the reader object.

import scipy.io
import pandas as pd
import numpy as np
from datetime import datetime, timedelta

class MatDataToCSV():

    def init(self):

        pass

    def convert_mat_tocsv(self):

        mat = scipy.io.loadmat('wiki.mat')

        instances = mat['wiki'][0][0][0].shape[1]
        columns = ["dob", "photo_taken", "full_path", "gender",\
                "name", "face_location", "face_score", "second_face_score"]
        df = pd.DataFrame(index = range(0,instances), columns = columns)

        for i in mat:
            if i == "wiki":
                current_array = mat[i][0][0]
                for j in range(len(current_array)):
                    df[columns[j]] = pd.DataFrame(current_array[j][0])
        return df

How can I export a matrix as a CSV file?, I have a 320x2 matrix with doubles. I want to save it in a CSV file in the following pattern: Use "writematrix" to export matrix data as a CSV file instead. Being a Python user coming to Matlab I was a bit shocked to find that csvwrite truncates the data output. MATLAB > Data Import and Analysis > Large Files and Big Data� At times, you may need to import Excel files into Python. If that’s the case, you can check the following tutorial that explains how to import an Excel file into Python. Once you imported your file into Python, you can start calculating some statistics using pandas. Alternatively, you can easily export pandas DataFrame into a CSV.

How to import, save and use data in multiple CSV files?, Learn more about csv files, importing csv, reading data from csv. I have a problem with importing csv files in Matlab. I have 3 CSV files with each And you can see in Python is easy to read CSV files lol MATLAB > Data Import and Analysis > Data Import and Export > Standard File Formats > Text Files� readtable('myfile.csv'); this generates a warning -> ' Warning: Column headers from the file were modified to make them valid MATLAB identifiers before creating variable names for the table. The original column headers are saved in the VariableDescriptions property.

Importing data in python Read mat file, Visit complete course on Data Science with Python Importing data in python Read mat file Duration: 4:27 Posted: 4 Jul 2017 However, this ability to skip over leading rows does not help the user read the strings as they asked. It would, though, allow for the possibility of fopen() the file, fgetl() one line, fclose(), split the input line to get the column headers, then csvread() the file telling it to skip the first row.

File IO (scipy.io) — SciPy v1.5.2 Reference Guide, Save a dictionary of names and arrays into a MATLAB-style .mat file. You may have a .mat file that you want to read into SciPy. Or, you want to pass some We can load this in Python: >>> rate, data). Write a NumPy array as a WAV file. SPM stores a file in .mat and .dat format. structure is saved in .mat and .dat file contain actual data. Please tell me way to use both of these files and convert to CSV. Also, how I can retrieve the 4 trials in my data.

Comments
  • consider using HDF5, e.g. see h5py and corresponding matlab functions
  • how do you propose to save different variables into a single CSV file?
  • I was hoping there was a way to write all of the variables and their corresponding values into a type of data matrix if you will that I can then import into IBM SPSS Modeler to conduct some analysis on the data. I was hoping to avoid iterating over the entire dictionary variable until all variables have been read because I am new to Python and know this would take a understanding of logic that I feel I don't have in the language. Will look into understanding HDF5 and any other suggestions would be greatly appreciated. Thanks!
  • with open('mycsvfile.csv','wb') as f: w = csv.writer(f) w.writerows(mat.items()) gives me a csv file with the array variable name and the first value of the array, does anyone know a way to use a command similar to this to obtain all values from the corresponding arrays in the dictionary?
  • Can you edit your question to contain that information?
  • I got this error 'dict' object has no attribute 'iteritems'.
  • If you’re using Python 3.x, it should be .items() instead of .iteritems()