How do I exclude the first column in my array?-CodePudding

I'm trying to plot a graph of mean time period against load, the first column in my array is load and I want to exlude it from my mean calculation.

[[0.2  0.96 0.94 0.91 0.69  nan  nan  nan  nan  nan  nan]
 [0.3  1.15 1.09 1.19 1.19 1.31 0.97 0.97  nan  nan  nan]
 [0.4  1.29 1.28 1.31 1.21  nan  nan  nan  nan  nan  nan]
 [0.5  1.54 1.43 1.45 1.37 1.35 1.29  nan  nan  nan  nan]
 [0.75 1.68 1.53 1.68 1.75 1.8  1.78  nan  nan  nan  nan]
 [1.   1.93 2.04 1.91 1.94  nan  nan  nan  nan  nan  nan]]

#define the function 
def clean_array(data):
    """Return a shortened array with any nans removed"""
    return data[np.logical_not(np.isnan(data))]

clean_array(data[0]).mean(), clean_array(data[0]).std(ddof=1)

(0.74, 0.32070235421649157)

CodePudding user response：

simply slice the array and save it a new and then apply mean on it.

np.array(data)[:,1:]

CodePudding user response：

If all you're trying to do is remove the first column from every data list within your list, you can remove the first element in each list like so:

# assuming a structure of [[],[]]     
data = [x.remove(0) for x in data]

This is list comprehension, essentially creating a new list of lists where for each element in your data object, you remove the first element and leave the rest of the list unchanged!