Python: how can I read data from files and assign it to an array? error":could not broadcast input array from shape"

Question

I have the following MATLAB code that works fine using text data files, now I am trying to rewrite it using Python but running into errors. I have results that I am trying to apply some calculations on (perform data analysis). My results are in the format of binary files and I have a specific package I am using to help me import the data. For example, here ne is a 1024x256 array with 159 number of files printed per each iteration. So, in MATLAB I can simply do the following:

% Load data:
frame = 6; % how many number of output files
ne_bg = load([DirPath '/ne_unpert.txt']); 
ne_p = load([DirPath '/ne_' num2str(frame) '.txt']);

% perform calculations on data:
ne = ne_bg + ne_p;

dn_over_n = ne_p ./ ne;

Since MATLAB deals easily with multi-dimensional arrays and matrices, I am struggling to interpret that to python.

My Python code:

import numpy as np
import matplotlib as mpl
import matplotlib.pyplot as plt
import matplotlib.cm as cm
import matplotlib.gridspec as gridspec
import matplotlib.colors as colors
import matplotlib.patches as patches

import scipy.optimize as opt
from scipy.special import erf, comb, gamma, gammainc
import scipy.constants as const
from scipy.integrate import odeint
import sys
from glob import glob
from mpl_toolkits.axes_grid1 import make_axes_locatable

import Package as pg

# Initialize sizes
ne = np.zeros((1024,256))
ne_p = np.zeros((1024,256))

# Data
data = pg.GData('ne_p.bp')
dg = pg.GInterpModal(data, 2, 'ms')
#dg.interpolate(overwrite=True)
ne_p = data.getValues() 

data = pg.GData('ne0.gkyl')
dg = pg.GInterpModal(data, 2, 'ms')
#dg.interpolate(overwrite=True)
ne_bg = data.getValues()

for i in range(1,159): # would like to look at files start from 1 to 159 not 0
    data = pg.GData('ne{:d}.gkyl'.format(i))
    dg = pg.GInterpModal(data, 2, 'ms')
    ne[i,:] = data.getValues() # ERROR HERE
    
    
dn_over_n = ne_p/ne # get 
....

Error message:

ValueError                                Traceback (most recent call last)
 in 
     48     dg = pg.GInterpModal(data, 2, 'ms')
     49     #dg.interpolate(overwrite=True)
---> 50     ne[i,:] = data.getValues()
  

ValueError: could not broadcast input array from shape (1024,256,1) into shape (256)

Can someone show me how to fix this and explain what it means?

Python: how can I read data from files and assign it to an array? error":could not broadcast input array from shape"

0 Answers