Revision history [back]
 | 1 | initial version |
Try
ZZ(y).inverse_mod(p)
| | 2 | No.2 Revision |
TryIf you define
y = np.int(tmp)
then do
ZZ(y).inverse_mod(p)
Better: directly define
y = ZZ(tmp)
and then do
y.inverse_mod(p)
| | 3 | No.3 Revision |
If (Edited to answer the follow-up question posted as a comment.)
Your code uses numpy, which uses Python's int type.
Sage has its own type of integers, in addition to Python integers.
Sage methods such as inverse_mod are implemented for Sage integers, not Python integers.
You can convert a Python integer k to a Sage integer by calling Integer(k) or ZZ(k).
So, if you definedefine, as in your code,
y = np.int(tmp)
then dochange the last line to
ZZ(y).inverse_mod(p)
Better: directly define
y = ZZ(tmp)
and then do
y.inverse_mod(p)
Now, you might want to avoid numpy altogether and work with native Sage matrices and vectors.
You can initialize a matrix or vector by specifying the base ring (eg ZZ, QQ, etc), the dimension, and the entries. If you don't provide entries, you get a zero matrix or vector. Matrices and vectors are mutable by default.
Rows, columns, and vector components are indexed from 0 rather than 1.
sage: a = matrix(ZZ, 3)
sage: a
[0 0 0]
[0 0 0]
[0 0 0]
sage: a[0, 0] = 4
sage: a
[4 0 0]
[0 0 0]
[0 0 0]
sage: v = vector(ZZ, 3)
sage: v
(0, 0, 0)
sage: v[1] = 2
sage: v
(0, 2, 0)
sage: a * v
(0, 0, 0)
You can find lots more information and examples in the documentation and tutorials, eg
http://doc.sagemath.org/html/en/tutorial/tour_linalg.html
See also the quick reference manual
https://wiki.sagemath.org/quickref?action=AttachFile&do=get&target=quickref-linalg.pdf
or query your favourite web search engine for [sagemath linear algebra].
