Reputation: 1966
I've got a simple question which I couldn't understand why it is the case for me . I'm reading two matrices A and B (which are 24*20)and calculate subtraction matrix of them and save it then I calculate MAPE(Mean Absolute Percentage Error). The problem is when I read them via Pandas
and apply following formula on subtraction matrix:
I've got production of this formula for each columns as 'series'
:
0 2.252708
1 1.727362
2 1.928928
3 1.562168
4 2.015080
5 2.760333
6 1.497950
7 1.047574
8 1.078431
9 1.065895
10 1.159555
11 0.937553
12 -0.130836
13 -0.090051
14 0.919025
15 0.094861
16 0.839204
17 -0.880221
18 -1.571482
19 -0.400643
dtype: float64
while via Numpy
I've got just one right answer.
17.813396179645633
Following is my code:
# Import and call the needed libraries
import numpy as np
import pandas as pd
#A = np.zeros((24,20))
#B = np.zeros((24,20))
A = pd.read_csv('D:\A.csv', header=None)
B = pd.read_csv('D:\B.csv', header=None)
#A = np.loadtxt('D:\A.csv', delimiter=',' )
#B = np.loadtxt('D:\B.csv', delimiter=',' )
delta1a = A - B
df_delta1a = pd.DataFrame(delta1a, index=None)
df_delta1a.to_csv(f'Subtraction_Matrix_1a_.csv', na_rep='nan', encoding='utf-8', index=False)
#MAPE formula
mape_plot_1a = 100 *( 1 - np.abs( ( delta1a) / A) )
mape_1a = 100 *( np.sum( 1 - np.abs( delta1a / A) ) )/480
print(mape_1a)
mape_percentage_1a = ("%.2f%%" % mape_1a)
So how can I read matrices via Pandas
and get right unique result after applying formula? why Pandas
return 'series'
and consequently I face following error:
TypeError: cannot convert the series to <class 'float'>
I'm wondering if my case is converting from Pandas
to Numpy
arrays or another issue since I've checked there are some answers like this and that but I couldn't fix it.
Upvotes: 0
Views: 101
Reputation: 142651
pandas
works rather with rows or columns, not with matrix.
But you can sum values in your Series
to get expected value
I took your values but they can be little rounded (pandas display little rounded values) so result is little different.
import pandas as pd
data = pd.Series([2.252708, 1.727362, 1.928928, 1.562168, 2.01508, 2.760333, 1.49795, 1.047574, 1.078431, 1.065895, 1.159555, 0.937553, -0.130836, -0.090051, 0.919025, 0.094861, 0.839204, -0.880221, -1.571482, -0.400643])
print(data.sum())
17.813394000000006
Upvotes: 1