Why do comparisons of NaN values behave differently from all other values? That is, all comparisons with the operators ==, <=, >=, <, > where one or both values is NaN returns false, contrary to the behaviour of all other values. I suppose this simplifies numerical computations in some way, but I couldn't find an explicitly stated reaso...
We are in the process of migrating Access 2007 to SQL 2005. We have a table with about 200 columns of float fields. Some of the fields have values of positive infinity or negative infinity ( 1.#INF or -1.#INF when viewed in Access ). Is there a way to clean this day or identify this data so we can report back to the owners the bad r...
Is there a command in MATLAB that allows me to find all NaN (Not-a-Number) elements inside an array? ...
How to set blank instead of NaN in jqGrid cells ? Using formatter ? Is there an example? ...
Short question, why do Assert.AreEqual(1.0, double.NaN, 0.0) pass when Assert.AreEqual(1.0, double.NaN) do not? Is it an error in MSTest or am I missing something here? Best regards, Egil. Update: Should probably add, that the reason behind my question is, that I have a bunch of unit tests that unfortunately passed due to the result o...
I am converting four bytes to float and I'm getting NaN as a result, but I want the value 0.0. What am I doing wrong? This is my code: public class abc { public static void main(String[] args) { int[] arry = { 255, 255, 255, 255 }; int num = ((arry[0] << 24) & 0xFF000000) | ((arry[1] << 16) & 0xFF0000) | ((...
Hello all, It is often hard to find the origin of a NaN, since it can happen at any step of a computation and propagate itself. So is it possible to make a C++ program halt when a computation returns NaN or inf? The best in my opinion would be to have a crash with a nice error message: Foo: NaN encoutered at Foo.c:624 Is something li...
Anyone have any experience with MDSJ? The following input produces only NaN results and I can't figure out why. The documentation is pretty sparse. import mdsj.Data; import mdsj.MDSJ; public class MDSJDemo { public static void main(String[] args) { double[][] input = { {78.0, 60....
I'm trying to add the values of two arrays in javascript eg. [1,2,1] + [3,2,3,4] The answer should be 4,4,4,4 but I'm either getting 4,4,4 or 4,4,4,NaN if I change the 1st array length to 4. I know a 4th number needs to be in the 1st array, but i can't figure out how to tell javascript to make it 0 rather then undefined if there i...
I would like to do element wise addition over matrices while skipping NaN values. MATLAB and Octave have nansum, but it does column wise addition within a matrix. Let: a = NaN * zeros(3) b = ones(3) I want: c = nan+(a, b) and c = b and: d = nan+(a,a) and d = a ...
I have the following two functions... function splitTitleString(titleText) { var titleText = titleText; var temp = new Array(); temp = titleText.split(' - '); var now = new Date().getTime(); var warningExpResp = 7200000; var expRespDateTimeTicks = 0; var slaDateTimeTicks = 0; if(temp[0].length > 0) ...
I would like to have some kind of project-wide fail fast mechanism (maybe a RuntimeException) for any code that causes assignment of NaN. In my project NaN is never a valid value. I realise I could add asserts (using isNaN) or other tests throughout but I want to know if there is a more elegant way. ...
The documentation for java.lang.Double.NaN says that it is A constant holding a Not-a-Number (NaN) value of type double. It is equivalent to the value returned by Double.longBitsToDouble(0x7ff8000000000000L). This seems to imply there are others. If so, how do I get hold of them, and can this be done portably? To be clear, I woul...
In C# .NET, what is the fastest way to initialize an array of doubles to NaN? Here is how I am presently initializing an array with many elements. int length = array.Length; for(int i = 0; i < length; i++) { array[i] = double.NaN; } Is there a faster way? ...
Hi, I have written the following sample code to find the harmonic value of N. (1+1/2+1/3+...1/N). Read the comments in the code written in BOLD and help me to find why is this happening. #include <stdio.h> float harmonic(float n, float har) { if(n==0) { return 0; } if(n==1) { printf("%f\n", har+1.0f);***/...
I don't know how to explain my problem.... but I have two RRD files: a.rrd b.rrd I'm trying to sum both of the files and STACK them up in the graph. like: my $bla = RRDs::graph "-", "--title","Test", "--imgformat=PNG", "--width=680", "--height=200", "DEF:Default0_=a.rrd:default:AVERAGE", "DEF:Real0_=a.rrd:re...
Forgive me if this is a dumb beginners problem, but I really don't get it. I have a member variable declared like so: public Double Value; When I assign 3.14159265 to Value and try to compute the sine of it, this happens: system.out.println(Value.toString()); //outputs 3.14159265 Value = Math.sin(Value); system.out.println(Value.toS...
Why am I getting this result? [TestMethod] public void nan_test() { Assert.AreEqual(1, double.NaN, 1E-1); <-- Passes Assert.AreEqual(1, double.NaN); <-- Fails } What difference does the delta have in asserting NaN equals a number? Surely it should always return false. I am aware of IsNaN, but that's not useful here (see ...
As the question states, I am using the MIPSPRo C compiler, and I have an operation that will return NaN for some data sets where both the numerator and denom are zero. How do I keep this from happening? ...
i'm trying to determine if a color has been supplied as an optional argument to a function. in order to determine this, i'm simply writing if(color){...} and supplying NaN if i don't want there to be a color. however, it seems that the color black (0x000000) also equates to NaN. how can i determine if a supplied color number argument ...