Running a python script in matlab
90 Ansichten (letzte 30 Tage)
Ältere Kommentare anzeigen
Tom Leblicq
am 15 Jan. 2013
Kommentiert: M Al Mamun
am 14 Okt. 2021
Hi, I tried to run a python script in matlab. I used the function system.So fa so good.
The pyhton script uses two input variables. In matlab I can enter one and then it runs without problems but when I try to enter two separate variables I always get an error.
systemCommand = ['python sqd.py ',num2str(a),num2str(omtrek)]
[status, result] = system(systemCommand);
This is the error:
status =
1
result =
Traceback (most recent call last):
File "sqd.py", line 10, in <module>
sys.stdout.write(str(squared(x)))
TypeError: squared() takes exactly 2 arguments (1 given)
Can someone help me?
Thanks!
1 Kommentar
Charles
am 29 Aug. 2017
This is interesting I am new to python, and I am trying to to do the dame thing Does the solution in fact work? I am keen to try it. I literally do not know python at all, neither am I am a programmer but I find it all fascinating and I move forward by trail and error. Some how I make progress. I will try this, but what infrastructure do you have? I have Matlab, 2017a and Python 3.6 Do i need anything else? I am reading that the former does not support the latter. Any thoughts?
Akzeptierte Antwort
Friedrich
am 16 Jan. 2013
Bearbeitet: Friedrich
am 16 Jan. 2013
Hi,
when modifying your script to:
import sys
def squared(a,omtrek):
b = (omtrek/2)-a
return b
if __name__ == '__main__':
x = float(sys.argv[1])
y = float(sys.argv[2])
sys.stdout.write(str(squared(x,y)))
and calling it from MATLAB:
>>!C:\Python32\python.exe sqd.py 1 2
it works fine for me. Or in your way:
>> a = 1
>> omtrek = 2
>>systemCommand = ['C:\Python32\python.exe sqd.py ',num2str(a),' ',num2str(omtrek)]
>> system(systemCommand)
0.0
ans =
0
1 Kommentar
Aravind Sasikumar
am 18 Apr. 2016
Bearbeitet: Aravind Sasikumar
am 18 Apr. 2016
Hello, The above code works for me too. The program is running but I am not able to get back the value of b in Matlab. I want to perform further calculations with the value of b.
import sys
def add(a,c):
b=a+c
return b
if _name_ == 'main':
x=float(sys.argv[1])
y=float(sys.argv[2])
sys.stdout.write(str(add(x,y)))
Why am I not getting the value of b back in matlab ?
Weitere Antworten (7)
Bo Li
am 18 Apr. 2016
Why not using Python Interface?
The MATLAB statement can be as simple as following:
>> b=py.sqd.squared(10,30)
1 Kommentar
Shashank Prasanna
am 15 Jan. 2013
Could you try the above with a space between the two arguments?
systemCommand = ['python sqd.py ',num2str(a),' ',num2str(omtrek)]
0 Kommentare
Aysha Ashraf
am 21 Dez. 2017
Can any one help me how to integrate this python code to matlab, i want to run this python program in matlab...
#Load dependencies import pandas as pd import numpy as np from sklearn.preprocessing import StandardScaler from matplotlib import* import matplotlib.pyplot as plt from matplotlib.cm import register_cmap from matplotlib.mlab import PCA from sklearn.decomposition import PCA
from scipy import stats #from wpca import PCA from sklearn.decomposition import PCA as sklearnPCA import seaborn
#Load movie names and movie ratings movies = pd.read_csv('movies.csv') ratings = pd.read_csv('ratings.csv') ratings.drop(['timestamp'], axis=1, inplace=True) # def replace_name(x): return movies[movies['movieId']==x].title.values[0] # ratings.movieId = ratings.movieId.map(replace_name) # M = ratings.pivot_table(index=['userId'], columns=['movieId'], values='rating') m = M.shape #posesall = pd.read_csv('FileName_Poses.csv') df1 = M.replace(np.nan, 0, regex=True) X_std = StandardScaler().fit_transform(movies) #Step 2: Covariance Matrix and Eigendecomposition mean_vec = np.mean(X_std, axis=0) cov_mat = (X_std - mean_vec).T.dot((X_std - mean_vec)) / (X_std.shape[0]-1) print('Covariance matrix \n%s' %cov_mat) print('NumPy covariance matrix: \n%s' %np.cov(X_std.T)) #Perform eigendecomposition on covariance matrix cov_mat = np.cov(X_std.T) eig_vals, eig_vecs = np.linalg.eig(cov_mat) print('Eigenvectors \n%s' %eig_vecs) print('\nEigenvalues \n%s' %eig_vals) # Step 3: Selecting Principal Components # Visually confirm that the list is correctly sorted by decreasing eigenvalues eig_pairs = [(np.abs(eig_vals[i]), eig_vecs[:,i]) for i in range(len(eig_vals))] print('Eigenvalues in descending order:') for i in eig_pairs: print(i[0]) pca = PCA(n_components = 93) All_poses_pca = pca.fit_transform(movies) Variance = (pca.explained_variance_ratio_)
#Explained variance pca = PCA().fit(X_std) plt.plot(np.cumsum(pca.explained_variance_ratio_)) plt.title('Scree Plot') plt.xlabel('Number of principal components') plt.ylabel('Cumulative explained variance') plt.show()
0 Kommentare
Yodish
am 12 Apr. 2018
It works for me as well, but it is very slow. It takes 0.2 sec to call a sum function from Python
Any ideas on how to speed it up? Where is the bottle neck?
0 Kommentare
Agapi Dav
am 31 Jul. 2018
Hello everyone! I have some images read in matlab and I want to process them in python and them return them to matlab for further processing.
Everything with the systemCommand works, however, even though I can import variables from matlab to python, because they are already in the workspace, I cannot return variables (e.g. images) back to matlab, when running the python script. Till now, in order to make it work, I save the python-processed images and then read them again from matlab.
I would like to ask if there is a more efficient way. In other words, in the example of Tom Leblicq, I would like to return the parameter b in matlab for further processing.
Thank you in advance!
1 Kommentar
Abdelwahab Afifi
am 12 Jan. 2021
The following command will return b in the workspace of MATLAB
b=py.sqd.squared(2)
Siehe auch
Kategorien
Mehr zu Call Python from MATLAB finden Sie in Help Center und File Exchange
Community Treasure Hunt
Find the treasures in MATLAB Central and discover how the community can help you!
Start Hunting!