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Select statement to find duplicates on certain fields
... of fields for which there are multiple records, you can use..
select field1,field2,field3, count(*)
from table_name
group by field1,field2,field3
having count(*) > 1
Check this link for more information on how to delete the rows.
http://support.microsoft.com/kb/139444
There should be a cr...
HtmlString vs. MvcHtmlString
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118
HtmlString only exists in ASP.NET 4.
MvcHtmlString was a compatibility shim added to MVC 2 to...
How to check whether a pandas DataFrame is empty?
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edited Dec 15 '17 at 17:37
Dave Thomas
1,38922 gold badges1010 silver badges1616 bronze badges
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Finding the index of elements based on a condition using python list comprehension
...nstead of a list.
>>> import numpy
>>> a = numpy.array([1, 2, 3, 1, 2, 3])
>>> a
array([1, 2, 3, 1, 2, 3])
>>> numpy.where(a > 2)
(array([2, 5]),)
>>> a > 2
array([False, False, True, False, False, True], dtype=bool)
>>> a[numpy.where(a ...
Creating a zero-filled pandas data frame
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140
You can try this:
d = pd.DataFrame(0, index=np.arange(len(data)), columns=feature_list)
...
Specify custom Date format for colClasses argument in read.table/read.csv
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159
You can write your own function that accepts a string and converts it to a Date using the form...
Is there a foreach in MATLAB? If so, how does it behave if the underlying data changes?
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147
MATLAB's FOR loop is static in nature; you cannot modify the loop variable between iterations,...
Python Matplotlib figure title overlaps axes label when using twiny
...ther it is a new feature in later versions of matplotlib, but at least for 1.3.1, this is simply:
plt.title(figure_title, y=1.08)
This also works for plt.suptitle(), but not (yet) for plt.xlabel(), etc.
share
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Regex how to match an optional character
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Use
[A-Z]?
to make the letter optional. {1} is redundant. (Of course you could also write [A-Z]{0,1} which would mean the same, but that's what the ? is there for.)
You could improve your regex to
^([0-9]{5})+\s+([A-Z]?)\s+([A-Z])([0-9]{3})([0-9]{3})([A-Z]{3})([A-...
ActiveRecord, has_many :through, and Polymorphic Associations
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162
There is a known issue with Rails 3.1.1 that breaks this functionality. If you are having this...