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LINQ - Left Join, Group By, and Count
...;t.ChildID != null didn't work for me. The result was always a null object and Resharper complained that the expression was always true. So I used (t => t != null) and that worked for me.
– Joe
Dec 2 '10 at 1:35
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:after vs. ::after
Is there any functional difference between the CSS 2.1 :after and the CSS 3 ::after pseudo-selectors (other than ::after not being supported in older browsers)? Is there any practical reason to use the newer specification?
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Default visibility for C# classes and members (fields, methods, etc.)?
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All of the information you are looking for can be found here and here (thanks Reed Copsey):
From the first link:
Classes and structs that are declared directly within a namespace (in other words, that are not nested within other classes or structs) can be either public or internal...
JavaScript checking for null vs. undefined and difference between == and ===
...hey're falsey:
if (!a) {
// `a` is falsey, which includes `undefined` and `null`
// (and `""`, and `0`, and `NaN`, and [of course] `false`)
}
This is defined by ToBoolean in the spec.
...and what is the difference between the null and undefined?
They're both values usually used to i...
float64 with pandas to_csv
...r you can use the float_format key word of to_csv to hide it:
df.to_csv('pandasfile.csv', float_format='%.3f')
or, if you don't want 0.0001 to be rounded to zero:
df.to_csv('pandasfile.csv', float_format='%g')
will give you:
Bob,0.085
Alice,0.005
in your output file.
For an explanation of ...
IF statement: how to leave cell blank if condition is false (“” does not work)
...ce.
See this post for a few other options.
edit
To reflect the comments and what you ended up doing: Instead of evaluating to "" enter another value such as 'deleteme' and then search for 'deleteme' instead of blanks.
=IF(ISBLANK(C1),TRUE,(TRIM(C1)="deleteme"))
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How do I compare two strings in Perl?
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See perldoc perlop. Use lt, gt, eq, ne, and cmp as appropriate for string comparisons:
Binary eq returns true if the left argument is stringwise equal to the right argument.
Binary ne returns true if the left argument is stringwise not equal to the right argument....
C/C++ macro string concatenation
... It's more than a technicality - you can't concatenate L"a" and "b" to get L"ab", but you can concatenate L"a" and L"b" to get L"ab".
– MSalters
Mar 10 '11 at 8:59
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Microsoft Roslyn vs. CodeDom
...o Roslyn, but is only marginally related. Essentially, CodeDom is a simple and (somewhat) langage agnostic way to generate code that was added in .NET 1.0 to support designers (a la WinForms). Because CodeDom was an attempt at providing a unified model that can generate code in C#, VB, and other lan...
What is the difference between Fragment and FragmentActivity?
... inheritance differences, what are the main differences between Fragment and FragmentActivity ? To what scenarios are each class best suited? I'm trying to get an understanding of why both of these classes exist...
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