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Constructing pandas DataFrame from values in variables gives “ValueError: If using all scalar values
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The error message says that if you're passing scalar values, you have to pass an index. So you can either not use scalar values for the columns -- e.g. use a list:
>>> df = pd.DataFrame({'A': [a], 'B': [b]})
>>> df
A B
0 2 3
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Checking if a field contains a string
I'm looking for an operator, which allows me to check, if the value of a field contains a certain string.
10 Answers
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How do I draw a shadow under a UIView?
...e(-15, 20), 5);
but before
CGContextRestoreGState(currentContext);
So if you want the superclass's drawRect: to be 'wrapped' in a shadow, then how about if you rearrange your code like this?
- (void)drawRect:(CGRect)rect {
CGContextRef currentContext = UIGraphicsGetCurrentContext();
CG...
Convert a number range to another range, maintaining ratio
...)
NewValue = (((OldValue - OldMin) * NewRange) / OldRange) + NewMin
Or if you want to protect for the case where the old range is 0 (OldMin = OldMax):
OldRange = (OldMax - OldMin)
if (OldRange == 0)
NewValue = NewMin
else
{
NewRange = (NewMax - NewMin)
NewValue = (((OldValue - Old...
Which Eclipse files belong under version control?
...in - to force a reinitialization of the eclipse metadata. But this option, if checked, will remove your detailed launch parameters!)
project-dir/.project
project-dir/.classpath
project-dir/.settings/*
should be in your SCM (especially .project and .classpath according to the Eclipse documentatio...
Should I use Java's String.format() if performance is important?
....println("Time after for loop " + time);
}
}
Running the above for different N shows that both behave linearly, but String.format is 5-30 times slower.
The reason is that in the current implementation String.format first parses the input with regular expressions and then fills in the parame...
How to randomize (shuffle) a JavaScript array?
...nswer skips element 0, the condition should be i-- not --i. Also, the test if (i==0)... is superfluous since if i == 0 the while loop will never be entered. The call to Math.floor can be done faster using ...| 0. Either tempi or tempj can be removed and the value be directly assigned to myArray[i] o...
Array.Copy vs Buffer.BlockCopy
...time when you are copying primitive type arrays, or should you only use it if you're coding for performance? Is there anything inherently dangerous about using Buffer.BlockCopy over Array.Copy ?
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What is the difference between “git branch” and “git checkout -b”?
... I think that git branch does the same thing.
How do these two commands differ, if they differ at all?
7 Answers
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Linux: compute a single hash for a given folder & contents?
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One possible way would be:
sha1sum path/to/folder/* | sha1sum
If there is a whole directory tree, you're probably better off using find and xargs. One possible command would be
find path/to/folder -type f -print0 | sort -z | xargs -0 sha1sum | sha1sum
And, finally, if you also need ...