inequality

Testing for inequality in T-SQL

I've just come across this in a WHERE clause: AND NOT (t.id = @id) How does this compare with: AND t.id != @id Or with: AND t.id <> @id I'd always write the latter myself, but clearly someone else thinks differently. Is one going to perform any better than the other? I know that using <> or != is going to bust any hopes for usin...

Comparing IEEE floats and doubles for equality

What is the best method for comparing IEEE floats and doubles for equality? I have heard of several methods, but I wanted to see what the community thought. ...

Solving an inequality for minimum value

I'm working on a programming problem which boils down to a set of an equation and inequality: x[0]*a[0] + x[1]*a[1] + ... x[n]*a[n] >= D x[0]*b[0] + x[1]*b[1] + ... x[n]*b[n] = C I want to solve for the values of X that will give the absolute minimum of C, given the input D and lists and A and B consisting of a[0 - n] and b[0 - n ]. ...

How to solve a system of inequalities?

I've reduced my problem (table layout algorithm) to the following problem: Imagine I have N variables X1, X2, ..., XN. I also have some (undetermined) number of inequalities, like: X1 >= 2 x2 + X3 >= 13 etc. Each inequalities is a sum of one or more variables, and it is always compared to a constant by using the >= operator. I cannot ...

Which 'not equal' operator is preferable in mysql

Perhaps this is a stupid question but we've had some debate recently. Which of the two (semantically equivalent) ways is preferable to test for inequality: 'foo' != 'bar' 'foo' <> 'bar' The mysql documentation clearly indicates that there is no difference between them and yet some people seem to be attached to only doing it one way ...

Proving that a function f(n) belongs to a Big-Theta(g(n))

Its a exercise that ask to indicate the class Big-Theta(g(n)) the functions belongs to and to prove the assertion. In this case f(n) = (n^2+1)^10 By definition f(n) E Big-Theta(g(n)) <=> c1*g(n) < f(n) < c2*g(n), where c1 and c2 are two constants. I know that for this specific f(n) the Big-Theta is g(n^20) but I don't know who to prov...

how to effectively run two inequality filters on queries in app engine

I'm aware that app engine has the restriction of "Inequality Filters Are Allowed On One Property Only" as described here: http://code.google.com/appengine/docs/python/datastore/queriesandindexes.html#Introducing_Indexes However is there some way to essentially run two filters, or is this simply not possible? For instance, if I had an e...

!(ReferenceEquals()) vs != in Entity Framework 4

Unless a class specifically overrides the behavior defined for Object, ReferenceEquals and == do the same thing... compare references. In property setters, I have commonly used the pattern private MyType myProperty; public MyType MyProperty { set { if (myProperty != value) { myProperty = value; ...

Like PIVOT but values not discrete

A table lists multiple events where each event has four attributes (columns), call them A, B, C, P It would be simpleto pivot to get a table with columns for A, B, C, P=1, P=2, P=3, etc. However, I need the columns to be A, B, C, P<1, P<2, P<3, etc. In other words, if a row of the "simple" way were X, Y, Z, 7, 3, 5, 2 then what I actu...

event delegate (in)equality ?

Could someone explain the meaning of the following portion of code : private event UserChangedHandler m_UserChanged; public event UserChangedHandler UserChanged { add { if (m_UserChanged != value) { m_UserChanged += value; } } } thanks ...