516.sagews

x,y=var('x,y')

B = matrix([[x,y,1],[2,-3,1],[3,-2,1]])

B.determinant()

y - x + 5

B

[ x y 1] [-2 -4 1] [-3 -4 1]

B

[x y 1] [1 2 1] [1 3 1]

B.determinant()

1 - x

B

[x y 1] [1 1 1] [2 2 1]

B.determinant()

y - x

[ 1 5 3 3] [ 5 5 8 9] [ 7 8 10 30]

[ 1 0 0 474/31] [ 0 1 0 129/31] [ 0 0 1 -342/31]

Traceback (most recent call last): File "<stdin>", line 1, in <module> File "/home/sage/sagenb/sage_notebook/worksheets/leodimo/9/code/18.py", line 6, in <module> exec compile(ur'B.determinant()' + '\n', '', 'single') File "/home/sage/sage_install/sage-a/local/lib/python2.5/site-packages/SQLAlchemy-0.4.6-py2.5.egg/", line 1, in <module> File "matrix_rational_dense.pyx", line 813, in sage.matrix.matrix_rational_dense.Matrix_rational_dense.determinant (sage/matrix/matrix_rational_dense.c:9592) File "matrix_rational_dense.pyx", line 2420, in sage.matrix.matrix_rational_dense.Matrix_rational_dense._det_pari (sage/matrix/matrix_rational_dense.c:21567) ArithmeticError: self must be a square matrix

B

[ 1 2 3 10] [ 4 5 6 9] [ 7 8 9 30]

B.determinant()

Traceback (most recent call last): File "<stdin>", line 1, in <module> File "/home/sage/sagenb/sage_notebook/worksheets/leodimo/9/code/8.py", line 6, in <module> exec compile(ur'B.determinant()' + '\n', '', 'single') File "/home/sage/sage_install/sage-a/local/lib/python2.5/site-packages/SQLAlchemy-0.4.6-py2.5.egg/", line 1, in <module> File "matrix_rational_dense.pyx", line 813, in sage.matrix.matrix_rational_dense.Matrix_rational_dense.determinant (sage/matrix/matrix_rational_dense.c:9592) File "matrix_rational_dense.pyx", line 2420, in sage.matrix.matrix_rational_dense.Matrix_rational_dense._det_pari (sage/matrix/matrix_rational_dense.c:21567) ArithmeticError: self must be a square matrix