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Creating dataframe from a dictionary where entries have different lengths
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Here's a simple way to do that:
In[20]: my_dict = dict( A = np.array([1,2]), B = np.array([1,2,3,4]) )
In[21]: df = pd.DataFrame.from_dict(my_dict, orient='index')
In[22]: df
Out[22]:
0 1 2 3
A 1 2 NaN NaN
B 1 2 3 4
In[23]: df.transpose()
Out[23]: ...
How to remove all callbacks from a Handler?
I have a Handler from my sub-Activity that was called by the main Activity . This Handler is used by sub-classes to postDelay some Runnables, and I can't manage them. Now, in the onStop event, I need to remove them before finishing the Activity (somehow I called finish() , but it still call ...
Difference between initLoader and restartLoader in LoaderManager
...d I use one of the two and why?
That should (hopefully) be clear after my explanations above.
Configuration changes
A LoaderManager retains its state across configuration changes (including orientation changes) so you would think there's nothing left for us to do. Think again...
First of all,...
Resize image in PHP
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Thanks! Forgive my ignorance, but where would that sit in the code that I've already got, and where would the function call sit? Am I right in saying that where I've got my database INSERT, rather than inserting $n, I'd insert $img? Or would...
Inserting a PDF file in LaTeX
I am trying to insert a PDF or doc file as an appendix in my LaTeX file. Do you know how I can do this?
6 Answers
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How to do ToString for a possibly null object?
...n now have a succinct, cast-free version of the orignal method:
string s = myObj?.ToString() ?? "";
Or even using interpolation:
string s = $"{myObj}";
Original Answer:
string s = (myObj ?? String.Empty).ToString();
or
string s = (myObjc ?? "").ToString()
to be even more concise.
Unfortunately, ...
What is Activity.finish() method doing exactly?
... @Laurent onPause() and onStop() are not always called. See my observation in below answer
– Prakash
Sep 10 '15 at 17:40
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sh...
What is the difference between save and export in Docker?
... I already made some images (which was really fun!). Now I want to persist my work and came to the save and export commands, but I don't fully understand them.
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How do I ignore the initial load when watching model changes in AngularJS?
...p graph in the $scope.fieldcontainer property. After I get a response from my REST API (via $resource), I add a watch to 'fieldcontainer'. I am using this watch to detect if the page/entity is "dirty". Right now I'm making the save button bounce but really I want to make the save button invisible un...
How to include JavaScript file or library in Chrome console?
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@Vassilis use my answer bellow (stackoverflow.com/a/57814219/6553339) to avoid this error
– shmulik friedman
Sep 11 '19 at 17:42
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