Why am I getting vals=[vals[j] for j in usecols] IndexError: list index out of range

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#1

Hi , in my dat file i have 3 columns of data however the 3rd column is not loading when i include it in the code however when i delete it the other 2 columns do show. Thankyou! is there an easier way?? This is my code:

from matplotlib import pyplot as plt
import numpy as np
import scipy.optimize as opt
import pylab

my_files=['earthquake_data.dat']

for i in range(1):
    N=np.loadtxt(my_files[i],dtype=float, unpack=True, skiprows=1, usecols=(0))
    Mag=np.loadtxt(my_files[i],dtype=float, unpack=True, skiprows=1, usecols=(1))
    Mag_err=np.loadtxt(my_files[i],dtype=float, unpack=True, skiprows=1, usecols=(2))
#2

I’ve edited your post for readability. When you enter a code block into a forum post, please precede it with a separate line of three backticks and follow it with a separate line of three backticks to make it easier to read.

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#3

Welcome, vadgh.

Try removing (setting to False) the unpack argument.

#4

Hi sky020 It worked thanks!

#5

Is the code in your original post the exact code you are trying to run? If so, take the values out of the for loop, and change to this my_files='earthquake_data.dat', and remove the indexing. See if that changes any thing.