On 05/13/2017 11:16 AM, eryk sun wrote:
On Sat, May 13, 2017 at 1:33 PM, Stephen P. Molnar
<s.mol...@sbcglobal.net> wrote:
I am using Python 3.6 in Anaconda3 Spyder IDE.
I have two arrays:
X Y Z
a
0 0 0
2.059801 0 0
-1.203126 3.402953 0
-1.108639 -1.567853 2.715601
-0.938564 -1.32733 -2.299003
a_c
0.4283375 0.91755 0.208299
and want to subtract the value of the value of each column or the array a_c
from the each value in the corresponding column of array c.
Trying a_mm = a - a_c where a_mm is the new array results in the error
message:
ValueError: operands could not be broadcast together with shapes (3,5) (1,3)
My search for a solution has not been successful.
You've presented array `a` as if it's 5x3, but the error says it's
3x5. If it were actually 5x3, there would be no problem:
import numpy as np
a = np.array([[0, 0, 0],
[2.059801, 0, 0],
[-1.203126, 3.402953, 0],
[-1.108639, -1.567853, 2.715601],
[-0.938564, -1.32733, -2.299003]])
a_c = np.array([[0.4283375, 0.91755, 0.208299]])
>>> a.shape
(5, 3)
>>> a_c.shape
(1, 3)
>>> a - a_c
array([[-0.4283375, -0.91755 , -0.208299 ],
[ 1.6314635, -0.91755 , -0.208299 ],
[-1.6314635, 2.485403 , -0.208299 ],
[-1.5369765, -2.485403 , 2.507302 ],
[-1.3669015, -2.24488 , -2.507302 ]])
You can use the transpose of either array. For example, use `a.T` to
get the same number of columns, or use `a_c.T` to get the same number
of rows.
That solved the problem.
Many thanks.
--
Stephen P. Molnar, Ph.D. Life is a fuzzy set
www.molecular-modeling.net Stochastic and multivariate
(614)312-7528 (c)
Skype: smolnar1
_______________________________________________
Tutor maillist - Tutor@python.org
To unsubscribe or change subscription options:
https://mail.python.org/mailman/listinfo/tutor
