How to change variable from list to float

[Paul Barry]

The value in existattn is a single element list.  The single element is a
float, so just refer to it in your calculation, like so:

    siglevfromexist = 34.8 + existattn[0]

Regards.

Paul.

On 3 June 2017 at 15:42, Gary Barker <barkerg at davincibb.net> wrote:

> I have searched for a solution to this but have not found a suitable
> example.
>
> The attached code generates this error: Traceback (most recent call last):
>   File "calcsignal.py", line 7, in <module>
>     siglevfromexist = 34.8 + existattn
> TypeError: unsupported operand type(s) for +: 'float' and 'list'
>
> How do I convert the list variable (i.e. existattn) to a float?
>
> Operating details are:
> Python 3.4.2
> Debian 3.16.39-1+deb8u2 (2017-03-07) x86_64 GNU/Linux
>
> The following lines are the code in calcsignal.py:
> azdegpattrev = -47.40715077970316
> azattndic = {-0.9: [-0.55], -0.5: [-0.46], 3.5: [-21.0], 1.4: [-7.48],
> 5.5: [-25.0], 0.0: [0.0], 1.9: [-21.0], 13.0: [-38.0], 15.0: [-39.0], 3.6:
> [-25.0], 20.0: [-39.0], -1.4: [-7.48], 90.0: [-65.0], -0.4: [-0.39], 0.5:
> [-0.46], 0.1: [-0.04], 1.0: [-1.31], -90.0: [-65.0], 40.0: [-42.0], 180.0:
> [-65.0], 1.5: [-10.0], -1.2: [-3.69], 0.3: [-0.28], -0.3: [-0.28], 0.2:
> [-0.15], -0.1: [-0.04], 1.1: [-2.34], -180.0: [-65.0], -0.2: [-0.15], 1.2:
> [-3.69], -40.0: [-42.0], 0.4: [-0.39], -5.5: [-25.0], -1.5: [-10.0], -20.0:
> [-39.0], 0.9: [-0.55], -3.5: [-21.0], -1.9: [-21.0], -15.0: [-39.0], -13.0:
> [-38.0], 1.3: [-5.39], -1.3: [-5.39], -3.6: [-25.0], -1.0: [-1.31], -1.1:
> [-2.34]}
> azlist = [-0.9, -0.5, 3.5, 1.4, 5.5, 0.0, 1.9, 13.0, 15.0, 3.6, 20.0,
> -1.4, 90.0, -0.4, 0.5, 0.1, 1.0, -90.0, 40.0, 180.0, 1.5, -1.2, 0.3, -0.3,
> 0.2, -0.1, 1.1, -180.0, -0.2, 1.2, -40.0, 0.4, -5.5, -1.5, -20.0, 0.9,
> -3.5, -1.9, -15.0, -13.0, 1.3, -1.3, -3.6, -1.0, -1.1]
> azlist = [float(i) for i in azlist]
> closestaz = min(azlist, key=lambda x: abs(x - azdegpattrev))
> existattn = azattndic[closestaz]
> siglevfromexist = 34.8 + existattn
> --
> https://mail.python.org/mailman/listinfo/python-list
>



-- 
Paul Barry, t: @barrypj <https://twitter.com/barrypj> - w:
http://paulbarry.itcarlow.ie - e: paul.barry at itcarlow.ie
Lecturer, Computer Networking: Institute of Technology, Carlow, Ireland.