search for: precision

Hello. I don't know if you can help me but I try. I have a collection of objects, we suppose that they are 1000. After some works that I made I divided this collection in some clusters. Suppose to have obtained 50 clusters. For each cluster I found a particular value called Precision, where 0<Precision<1. Taken the firs cluster I want to compare his Precision with the precision of his complement that his obtained by the union of the remainder clusters. After this I want to take the second cluster and make the same thing comparing his precision with the precision of his co...

Hi, I am working with large numbers and identified that R looses precision for such high numbers. The precision is lost exactly when the number is equal or larger than 53 bits. See the following output which shows that the numbers below 53 bit have proper precision: > 2^53 [1] 9007199254740992 > 2^53-1 [1] 9007199254740991 > 2^53-2 [1] 9007199254740990 Now, se...

I'd like to start a discussion about how clang supports _Float16 for target architectures that don't have direct support for 16-bit floating point arithmetic. The current clang language extensions documentation says, "If half-precision instructions are unavailable, values will be promoted to single-precision, similar to the semantics of __fp16 except that the results will be stored in single-precision." This is somewhat vague (to me) as to what is meant by promotion of values, and the part about results being stored in singl...

Running Tomb Raider on Nouveau I found some flicker caused by ignoring precise modifiers on variables inside Nouveau. This series add precise/invariant handling to TGSI, which can be then used by drivers to disable certain unsafe optimisations which may otherwise alter calculations, which depend on having the same result across shaders. This series fixes this bug in Tomb Raider and one CTS test

I'm working on a shared library of C functions for use with R, and I want to create a matrix in R and pass it to the C routines. I know R computes and supposedly stores numerics in double precision, but when I create a matrix of random numerics using rnorm(), the values are displayed in single precision, and also exported in single precision when I pass them out to my C routines. An example is below: > a <- matrix(rnorm(16, mean=10, sd=4), nrow=4) > a [,1] [,2]...

I have prices that I am finding difficult to compare with ==, > and >, due to precision. For example: the numbers should match, with '==', but they differ in the magnitude of 1e-14 due to bunch of calculations that I run on them. Programming with java, I am used to implementing a function that compares the difference between the numbers to a pre determined precision factor. Th...

Hello, is there a possibilty in R to convert numbers (double precision, 64bit) into single precision ones (32bit). I need that for compatibility reasons. Until now I call a C application which casts a double to a float. float precision32(double value) { return (float)value; } But I want to use a R only method. What can I do? Kind regards, Sebastian

On Fri, 25 May 2012 14:00:01 -0500, <theora-request at xiph.org> wrote: > Message: 1 > Date: Fri, 25 May 2012 19:26:18 +0200 > From: Raphael Canut <nhwcodec at gmail.com> > Subject: [theora] NHW codec - improvement of precision > To: theora at xiph.org > Message-ID: > <CAKE58qHqSsrgJP4OX++eetMmT2WTv=8ZvfXoou7bWjOnbUSrAQ at mail.gmail.com> > Content-Type: text/plain; charset="iso-8859-1" > > Hello, > > Just contact you quickly as I have improved precision of my codec (a > little)...

Hi again, I have improved precision of my codec (on the encoder and decoder).I have also improved the -h1 quality setting.-Source code and binaries at http://nhwcodec.blogspot.com/-. I am still trying to improve precision of my codec, with keeping my low-complexity (fast) approach. I do not totally use the reference (and impressive)...

Hi: Is it possible to perform computations in quadruple precision (more generally, with more digits in the floating-point arithmetic than that allowed by double precision) in R? thanks, Ravi. [[alternative HTML version deleted]]

Hi All, Clang lacks support for the -fsingle-precision-constant flag. Are there specific reasons for this or is it just waiting to be implemented? This flag is especially important in the embedded world. From http://processors.wiki.ti.com/index.php/Floating_Point_Optimization#float_vs._double_vs._long_double : *Once all of your data is defined as f...

all subexpression inside an ir_assignment needs to be tagged as precise. Signed-off-by: Karol Herbst <karolherbst at gmail.com> --- src/mesa/state_tracker/st_glsl_to_tgsi.cpp | 80 ++++++++++++++++++++++++------ 1 file changed, 65 insertions(+), 15 deletions(-) diff --git a/src/mesa/state_tracker/st_glsl_to_tgsi.cpp b/src/mesa/state_tracker/st_glsl_to_tgsi.cpp index c5d2e0fcd2..19f90f21fe

...<- as.double( 7.785205408500864D-02) Error: unexpected symbol in " c14 <- as.double( 7.785205408500864D" The above "D" is used in Fortran language to indicate the memory starage mode. That is for instructing Fortran compiler to store such a REAL constant in DOUBLE PRECISION... am I right ? Since R cannot undestand numerical conatant post-fixed by the letter "D", I wonder how I can instruct R interpreter to store such a numerical constant reserving as muh memory as necessary so as to accommodate a double precision number. I noticed R accepts the folllowing...

Hi All, This is Lian Li from Oracle Labs in Brisbane Australia. We have developed a precise and highly efficient pointer analysis framework on top of LLVM, The approach is flow, context, and field sensitive, details are described in the two papers below: "Boosting the performance of flow-sensitive points-to analysis using value flow" (in ESEC-FSE 2011), and "Precise and

How precise is R numerically? For example I wrote the following function for calculating the volume of the ball inscribed in the unit cube in m dimensions. In order to see what happens in 40 dimensions, I created an output of 24 digits. But how many are precise? Thanks Josef Eschgf?ller Ferrara --------------------------------------- Vol = function (m) {if (m<=1) 1 else Vol(m-2)*pi/(m+m)}

Hi I am trying to use active record to copy some data. One of the entry I am copying is type interval (Postgres); however, it lose some precision after I copied that column. Here is what I did: @newData.elapsedtime = @oldData.elapsedtime @newData.save Result: both displayed as 00:00:02.453 in the table, however, if I use the following command to convert its value into float ( SELECT date_part(''epoch''::text, [table].ela...

...s32 registers are just a subregister in their Mips64 instance. def AT : MipsGPRReg< 1, "AT">, DwarfRegNum<[1]>; def AT_64 : Mips64GPRReg< 1, "AT", [AT]>; It gets more interesting with floating point where we have 3 different configurations, single precision, double precision aliased with single precision pair and straight double point precision. All of which share the same register name. /// Mips Single point precision FPU Registers def F0 : FPR< 0, "F0">, DwarfRegNum<[32]>; /// Mips Double point precision FPU Registers...

Hi, Why sum() on a 10-item vector produces a different value than its counterpart on a 2-item vector? I understand the problems related to the arithmetic precision in storing decimal numbers in binary format, but shouldn't the errors be equal regardless of the method used? See my example: > options(digits=22) > x=rep(.1,10) > x [1] 0.10000000000000001 0.10000000000000001 0.10000000000000001 [4] 0.10000000000000001 0.10000000000000001 0.100000...

This looks like the right idea to me too. It may sound a bit weird to do that per instruction, but d3d11 does that as well. (Some d3d versions just have a global flag basically forbidding or allowing any such fast math optimizations in the assembly, but I'm not actually sure everybody honors that without tesselation...) For 1/9: Reviewed-by: Roland Scheidegger <sroland at vmware.com>

On 11.06.2017 20:42, Karol Herbst wrote: > Running Tomb Raider on Nouveau I found some flicker caused by ignoring precise > modifiers on variables inside Nouveau. > > This series add precise/invariant handling to TGSI, which can be then used by > drivers to disable certain unsafe optimisations which may otherwise alter > calculations, which depend on having the same result