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Convert date to datetime in Python

You can use datetime.combine(date, time); for the time, you create a datetime.time object initialized to midnight.

How to fix “TypeError: len() of unsized object”

Use the arrays’ size attribute instead: You also probably want to use numpy.fromstring to take and convert the input string into an array:

“RuntimeError: Make sure the Graphviz executables are on your system’s path” after installing Graphviz 2.38

You should install the graphviz package in your system (not just the python package). On Ubuntu you should try:

Error NameError: name ‘np’ is not defined

As @aydow says, “change from numpy import * to import numpy as np“: Or don’t write np: Because, from numpy import *, Import every function in numpy, so np is not a function of numpy, so have to Import numpy like import numpy as np, Or, Remove np part of np.random.randint(low=10, high=30, size=6), and make it like this: random.randint(low=10, high=30, size=6), it’s all since random is a function of … Read more

No module named Image

Did you setup PIL module? Link You can try to reinstall it on your computer.

Convert datetime to Unix timestamp and convert it back in python

What you missed here is timezones. Presumably you’ve five hours off UTC, so 2013-09-01T11:00:00 local and 2013-09-01T06:00:00Z are the same time. You need to read the top of the datetime docs, which explain about timezones and “naive” and “aware” objects. If your original naive datetime was UTC, the way to recover it is to use … Read more

No numeric types to aggregate – change in groupby() behaviour?

How are you generating your data? See how the output shows that your data is of ‘object’ type? the groupby operations specifically check whether each column is a numeric dtype first. look ↑ Did you initialize an empty DataFrame first and then filled it? If so that’s probably why it changed with the new version … Read more