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Warning message: In `…` : invalid factor level, NA generated
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Here is a flexible approach, it can be used in all cases, in particular:
to affect only one column, or
the dataframe has been obtained from applying previous operations (e.g. not immediately opening a file, or creating a new data frame).
First, un-factorize a stri...
Exception.Message vs Exception.ToString()
...ntaining the exception type, the message (from before), a stack trace, and all of these things again for nested/inner exceptions. More precisely, the method returns the following:
ToString returns a representation of the current exception that is intended to be understood by humans. Where the excep...
AutoLayout with hidden UIViews?
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Would be nice to give a small example of how stack view handles this.
– lostintranslation
Sep 9 '16 at 19:47
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iOS Remote Debugging
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Yep, I'm already using this one. Finally! It sucks that the windows version of Safari does not have it though.
– Hyangelo
Sep 26 '12 at 18:05
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How to clone an InputStream?
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If all you want to do is read the same information more than once, and the input data is small enough to fit into memory, you can copy the data from your InputStream to a ByteArrayOutputStream.
Then you can obtain the associate...
How can I remove all text after a character in bash?
How can I remove all text after a character, in this case a colon (":"), in bash? Can I remove the colon, too? I have no idea how to.
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How do I parse JSON in Android? [duplicate]
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Android has all the tools you need to parse json built-in. Example follows, no need for GSON or anything like that.
Get your JSON:
Assume you have a json string
String result = "{\"someKey\":\"someValue\"}";
Create a JSONObject:
JS...
Where in memory are my variables stored in C?
...declared in functions), variables (in main function), pointers, and dynamically allocated space (using malloc and calloc) get stored in memory?
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Casperjs/PhantomJs vs Selenium
...ness of testing a finance application where the login screen is unintentionally broken and non-functional!
Note that the line between the two gets slightly blurred with the recent WebDriver support in the latest PhantomJS. It is now possible to quickly run the tests first using PhantomJS and then (...
Replacing Pandas or Numpy Nan with a None to use with MysqlDB
...s:
df1 = df.where(pd.notnull(df), None)
Note: this changes the dtype of all columns to object.
Example:
In [1]: df = pd.DataFrame([1, np.nan])
In [2]: df
Out[2]:
0
0 1
1 NaN
In [3]: df1 = df.where(pd.notnull(df), None)
In [4]: df1
Out[4]:
0
0 1
1 None
Note: what you ca...