Thank you, that was exactly the starting point I needed! I managed to get it working, now I just need to position everything and make it look good.

I wanted to try and make a small app to help with breathing exercises. I haven't done anything with animation/ui yet, so I was wondering if anyone could help me with a starting point. I want the animation to do the following:

1. Have a circle expand for x seconds
2. Pauze for y seconds
3. Have the circle contract in z seconds
4. Pauze for a seconds
5. Repeat for b minutes

Ultimately it would be nice to have all the settings and duration configurable in the ui, but changing the values directly in the script is no problem.

I thought the analog clock example would be a good starting point, but when I understood that one and tried to figure out how to use that approach for this use case, I got the feeling that the updating step would become more complex than necessary.

What would be a good starting point for this?

Just a stupid question, but shouldn't the background picture be an iPad instead of a MacBook ;) ?
The layout looks great.

In the ios contacts, you can add extra dates, for things like anniveraries. I'd like to use them to add birthdays of children, since they really don't need their own contact entry. The problem is that these dates don't end up in the birthday calendar, so I thought I'd use pythonista to construct such a calendar. Now, maybe I overlooked it, but I couldn't find a way to get to those extra dates, did I miss something?

If it's not possible to access them, I'll put the dates in the notes field and parse them, but that wouldn't be as elegant.

Also, think about e^x or e^-x or e^4 (without the brackets). For that you definitely need regular expressions.

import re

formula = re.sub(r'e\^(-?[x0-9.]+?)', 'exp(\1)', formula)

Something like that, haven't tested it, but should give you a start if you want to do something with re.

I guess you'd have to use regular expressions to preprocess the user input before you plot. You have to be careful how you do it though, because e^ should become exp and not e**.

A quick and dirty solution would be to print a line to tell the user to use ** instead of ^ etc.

I just installed stash (very cool!) and wanted to use pip to install pylint. It seemed to work, but when I tried to run it I got an error saying it needed astroid. When I tried to pip install that I got a 'Failed import test. Check for dependencies' error. From comments on the forum it seemed as it would be trivial to install pylint, am I doing something wrong?

Thank you very much, @JonB! It worked like a charm!

I did that for a couple of other modules, but forgot it for six 😕. I uninstalled with pip, but that doesn't change the error message. Useful link!

I added some traceback to the pip code and found out that the problem is that setuptools doesn't have a find_packages function. I don't understand exactly how this part of the code works, so now I'm stuck. There are people that managed to install pylint, any ideas?

So I found out that astroid needs logilab-commons and six. Logilab-commons also needs six. I installed six, no problem, but now I can't get logilab-commons to install.

I get this error:

Trying to run setup.py
Unable to locate package. Please try manual install
Removing setup files
Failed import test. Check for dependencies

I got the import error from astroid, but that one didn't specify a module. It said it extracted a requires file, but I couldn't find that. Maybe I should just google for the astroid dependencies then.