# Difference between U and U(t)

If I have

```
t = var('t')
U = function('U', t).function(t)
```

what is the difference between the expression *U* and *U(t)*. When should I use which?

Difference between U and U(t)

If I have

```
t = var('t')
U = function('U', t).function(t)
```

what is the difference between the expression *U* and *U(t)*. When should I use which?

0

Asked: **
2011-07-30 13:38:30 -0600
**

Seen: **89 times**

Last updated: **Sep 16 '11**

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