how to define var vector?

asked 10 years ago

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sage: a,b,c=var("a,b,c")
sage: v = vector(QQ, ["a", "b", "c"]);v
...
TypeError: unable to convert a to a rational

cannot run

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There are two errors in your code.

First: you define variables a,b,c , that's ok, but you use strings in the list of vector entries.

Second: a,b,c are elements of the symbolic ring and cannot be converted to elements of QQ

sage:  a,b,c=var("a,b,c");v = vector([a,b,c]);v

(a,b,c)

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Asked: 10 years ago

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Last updated: Oct 23 '14