# Vector multiplication

I would like to know why this procedure doesn't work

```
aa = list(var('delta_%d' % i) for i in (0..2))
c=n(matrix(1,3,(-0.5,0.2,.3)),2)
U = e^(c*transpose(aa))
show(U)
```

Vector multiplication

I would like to know why this procedure doesn't work

```
aa = list(var('delta_%d' % i) for i in (0..2))
c=n(matrix(1,3,(-0.5,0.2,.3)),2)
U = e^(c*transpose(aa))
show(U)
```

add a comment

1

For one, because you can't transpose `list`

s. Secondly, you should take the (single) entry of `c*aa`

.

```
aa = vector(var('delta_%d' % i) for i in (0..2))
c = n(matrix(1,3,(-0.5,0.2,.3)),2)
U = e^((c*aa)[0])
show(U)
```

$$e^{\left(-0.50 \delta_{0} + 0.19 \delta_{1} + 0.25 \delta_{2}\right)}$$

(Note that you specified 2 *bits* of precision with `n`

.)

Asked: **
2019-11-12 09:09:27 -0600
**

Seen: **46 times**

Last updated: **Nov 13 '19**

Efficient way to define many variables?

Creating an object of the Magmatic Algebras category

Computing basis of local artinian ring as a vector space.

Substituting a differential equation into an expression

How to plot a parabola (conic): y²=4ax

Using numerical solution from system of equations

Find all non-negative integer solutions of $a+b+c+d+e = 8$ in Sagemath

Copyright Sage, 2010. Some rights reserved under creative commons license. Content on this site is licensed under a Creative Commons Attribution Share Alike 3.0 license.