Search Results

Search found 3885 results on 156 pages for 'dot emacs'.

Page 47/156 | < Previous Page | 43 44 45 46 47 48 49 50 51 52 53 54  | Next Page >

• How to apply verification and validation on the following example

  - by user970696

  I have been following verification and validation questions here with my colleagues, yet we are unable to see the slight differences, probably caused by language barrier in technical English. An example: Requirement specification User wants to control the lights in 4 rooms by remote command sent from the UI for each room separately. Functional specification The UI will contain 4 checkboxes labelled according to rooms they control. When a checkbox is checked, the signal is sent to corresponding light. A green dot appears next to the checkbox When a checkbox is unchecked, the signal (turn off) is sent to corresponding light. A red dot appears next to the checkbox. Let me start with what I learned here: Verification, according to many great answers here, ensures that product reflects specified requirements - as functional spec is done by a producer based on requirements from customer, this one will be verified for completeness, correctness). Then design document will be checked against functional spec (it should design 4 checkboxes..), and the source code against design (is there a code for 4 checkboxes, functions to send the signals etc. - is it traceable to requirements). Okay, product is built and we need to test it, validate. Here comes our understanding trouble - validation should ensure the product meets requirements for its specific intended use which is basically business requirement (does it work? can I control the lights from the UI?) but testers will definitely work with the functional spec, making sure the checkboxes are there, working, labelled, etc. They are basically checking whether the requirements in functional spec were met in the final product, isn't that verification? (should not be, lets stick to ISO 12207 that only validation is the actual testing)

  Read the article

• How do you make slides for programming talks?

  - by Yuvi Masory

  I've given a few talks recently and I have not found a good way to make slides. Here are a few desirable characteristics for programming slides: They're slides. A standard emacs buffer won't do it. They have syntax highlighting for code. They support basic formatting, like font size and color and bullets. No fancy animations needed. The only animation I desire is one-by-one appearance of bullets. So far I have considered: Microsoft Office - out of the question for Linux users. OpenOffice.org - too much for my needs, code formatting/highlighting needs to be done externally and pasted in. On the plus side supports bullets, bullet-by-bullet animation, and font formatting. Emacs - Supports all the code formatting but I haven't found a slides mode that lets me transition from one chunk to another. HTML5 - I once made slides using html5rocks as a template. It supports everything, but is too hard and time-consuming the "throw together" a few slides before a minor talk. Also the html5-only features may not work on the podium computer's installed browser. Any suggestions for programs/techniques for making code-centric presentations?

  Read the article

• Law of Demeter confusion [duplicate]

  - by user2158382

  This question already has an answer here: Rails: Law of Demeter Confusion 4 answers I am reading a book called Rails AntiPatterns and they talk about using delegation to to avoid breaking the Law of Demeter. Here is their prime example: They believe that calling something like this in the controller is bad (and I agree) @street = @invoice.customer.address.street Their proposed solution is to do the following: class Customer has_one :address belongs_to :invoice def street address.street end end class Invoice has_one :customer def customer_street customer.street end end @street = @invoice.customer_street They are stating that since you only use one dot, you are not breaking the Law of Demeter here. I think this is incorrect, because you are still going through customer to go through address to get the invoice's street. I primarily got this idea from a blog post I read: http://www.dan-manges.com/blog/37 In the blog post the prime example is class Wallet attr_accessor :cash end class Customer has_one :wallet # attribute delegation def cash @wallet.cash end end class Paperboy def collect_money(customer, due_amount) if customer.cash < due_ammount raise InsufficientFundsError else customer.cash -= due_amount @collected_amount += due_amount end end end The blog post states that although there is only one dot customer.cash instead of customer.wallet.cash, this code still violates the Law of Demeter. Now in the Paperboy collect_money method, we don't have two dots, we just have one in "customer.cash". Has this delegation solved our problem? Not at all. If we look at the behavior, a paperboy is still reaching directly into a customer's wallet to get cash out. Can somebody help me clear the confusion. I have been searching for the past 2 days trying to let this topic sink in, but it is still confusing.

  Read the article

• HLSL What you get when you subtract world position from InvertViewProjection.Transform?

  - by cubrman

  In one of NVIDIA's Vertex shaders (the metal one) I found the following code: // transform object normals, tangents, & binormals to world-space: float4x4 WorldITXf : WorldInverseTranspose < string UIWidget="None"; >; // provide tranform from "view" or "eye" coords back to world-space: float4x4 ViewIXf : ViewInverse < string UIWidget="None"; >; ... float4 Po = float4(IN.Position.xyz,1); // homogeneous location coordinates float4 Pw = mul(Po,WorldXf); // convert to "world" space OUT.WorldView = normalize(ViewIXf[3].xyz - Pw.xyz); The term OUT.WorldView is subsequently used in a Pixel Shader to compute lighting: float3 Ln = normalize(IN.LightVec.xyz); float3 Nn = normalize(IN.WorldNormal); float3 Vn = normalize(IN.WorldView); float3 Hn = normalize(Vn + Ln); float4 litV = lit(dot(Ln,Nn),dot(Hn,Nn),SpecExpon); DiffuseContrib = litV.y * Kd * LightColor + AmbiColor; SpecularContrib = litV.z * LightColor; Can anyone tell me what exactly is WorldView here? And why do they add it to the normal?

  Read the article

• Rails: The Law of Demeter [duplicate]

  - by user2158382

  This question already has an answer here: Rails: Law of Demeter Confusion 4 answers I am reading a book called Rails AntiPatterns and they talk about using delegation to to avoid breaking the Law of Demeter. Here is their prime example: They believe that calling something like this in the controller is bad (and I agree) @street = @invoice.customer.address.street Their proposed solution is to do the following: class Customer has_one :address belongs_to :invoice def street address.street end end class Invoice has_one :customer def customer_street customer.street end end @street = @invoice.customer_street They are stating that since you only use one dot, you are not breaking the Law of Demeter here. I think this is incorrect, because you are still going through customer to go through address to get the invoice's street. I primarily got this idea from a blog post I read: http://www.dan-manges.com/blog/37 In the blog post the prime example is class Wallet attr_accessor :cash end class Customer has_one :wallet # attribute delegation def cash @wallet.cash end end class Paperboy def collect_money(customer, due_amount) if customer.cash < due_ammount raise InsufficientFundsError else customer.cash -= due_amount @collected_amount += due_amount end end end The blog post states that although there is only one dot customer.cash instead of customer.wallet.cash, this code still violates the Law of Demeter. Now in the Paperboy collect_money method, we don't have two dots, we just have one in "customer.cash". Has this delegation solved our problem? Not at all. If we look at the behavior, a paperboy is still reaching directly into a customer's wallet to get cash out. EDIT I completely understand and agree that this is still a violation and I need to create a method in Wallet called withdraw that handles the payment for me and that I should call that method inside the Customer class. What I don't get is that according to this process, my first example still violates the Law of Demeter because Invoice is still reaching directly into Customer to get the street. Can somebody help me clear the confusion. I have been searching for the past 2 days trying to let this topic sink in, but it is still confusing.

  Read the article

• How do Unity 12.04/Compiz bindings really work?

  - by Daniel

  There is a bewildering array of places to set bindings, all inconsistent with one another. E.g. in Unity's System Settings having the Ctrl-key highlight the mouse position is an on/off choice. I like the feature, but not on such a prominent key where I keep activating it accidentally. The keyboard shortcuts allow only one binding per command, where I might like a convenient one on the external keyboard and an emergency alternative for when I'm on the road. Keyboard custom shortcuts has a nice interface, but allows only key bindings — besides it doesn't seem to work for me. So I activated CCSM Commands. There I have the choice of key-, mouse- and/or edge bindings. Whereas some places in CCSM offers only one or two of these binding possibilities, randomly at the whim of the programmer. I have not found a way to differentiate a mouse-drag from a click. E.g. I want <SuperMouse1-drag anywhere on a window to move it, while if I don't drag, it should be raise-lower. On the title bar I want the same without needing the <Super key. Now I find raise-lower only in System Settings where I can't assign a mouse binding. If therefore in CCSM I fallback to only lower and put move on the same binding, the window already gets lowered on mouse down, and I can then invisibly move it. Very useful! I have <Altasciicircum get in the way of an Emacs binding, with some to me useless popup overlay. I can find it nowhere, so I can't turn it off. So how can I go without these frontends until they have matured, and instruct Compiz directly, for example in the way Emacs or Sawfish have keymaps, and separate ones for each context, with inheritance?

  Read the article

• Points around a circumference C#

  - by Lautaro

  Im trying to get a list of vectors that go around a circle, but i keep getting the circle to go around several times. I want one circel and the dots to be placed along its circumference. I want the first dot to start at 0 and the last dot to end just before 360. Also i need to be able to calculate the spacing by the ammount of points. List<Vector2> pointsInPath = new List<Vector2>(); private int ammountOfPoints = 5; private int blobbSize = 200; private Vector2 topLeft = new Vector2(100, 100); private Vector2 blobbCenter; private int endAngle = 50; private int angleIncrementation; public Blobb() { blobbCenter = new Vector2(blobbSize / 2, blobbSize / 2) + topLeft; angleIncrementation = endAngle / ammountOfPoints; for (int i = 0; i < ammountOfPoints; i++) { pointsInPath.Add(getPointByAngle(i * angleIncrementation, 100, blobbCenter)); // pointsInPath.Add(getPointByAngle(i * angleIncrementation, blobbSize / 2, blobbCenter)); } } private Vector2 getPointByAngle(float angle, float distance, Vector2 centre) { return new Vector2((float)(distance * Math.Cos(angle) ), (float)(distance * Math.Sin(angle))) + centre ; }

  Read the article

• Laser range finder, what language to use? Beginner advice

  - by DrOnline

  I hope this is the right place. I am a programming beginner, and I want to make a laser range finder, and I need advice about how to proceed etc. In a few weeks I will get a lot of dirt cheap 3-5V lasers and some cheap usb webcams. I will point the laser and webcam in parallel, and somehow use trigonometry and programming to determined distance. I have seen online that others made done it this way, I have purposefully not looked at the details too much because I want to develop it on my own, and learn, but I know the general outline. I have a general idea of how to proceed. The program loads in a picture from the webcam, and I dunno how images work really, but I imagine there is a format that is basically an array of RGB values.. is this right? I will load in the red values, and find the most red one. I know the height difference between the laser and the cam. I know the center dot in the image, I know the redmost dot. I'm sure there's some way to figure out some range there. TO THE POINT: 1) Is my reasoning sound thus far, especially in terms of image analysis? I don't need complete solutions, just general points 2) What I need to figure out, is what platform to use. I have an arduino... apparently, I've read it's too weak to process images. Read that online. I know some C I know some Python I have Matlab. Which is the best option? I do not need high sampling rates, I have not decided on whether it should be automated or whether I should make a GUI with a button to press for samples. I will keep it simple and expand I think. I also do not need it to be super accurate, I'm just having fun here. Advice!

  Read the article

• GLSL Atmospheric Scattering Issue

  - by mtf1200

  I am attempting to use Sean O'Neil's shaders to accomplish atmospheric scattering. For now I am just using SkyFromSpace and GroundFromSpace. The atmosphere works fine but the planet itself is just a giant dark sphere with a white blotch that follows the camera. I think the problem might rest in the "v3Attenuation" variable as when this is removed the sphere is show (albeit without scattering). Here is the vertex shader. Thanks for the time! uniform mat4 g_WorldViewProjectionMatrix; uniform mat4 g_WorldMatrix; uniform vec3 m_v3CameraPos; // The camera's current position uniform vec3 m_v3LightPos; // The direction vector to the light source uniform vec3 m_v3InvWavelength; // 1 / pow(wavelength, 4) for the red, green, and blue channels uniform float m_fCameraHeight; // The camera's current height uniform float m_fCameraHeight2; // fCameraHeight^2 uniform float m_fOuterRadius; // The outer (atmosphere) radius uniform float m_fOuterRadius2; // fOuterRadius^2 uniform float m_fInnerRadius; // The inner (planetary) radius uniform float m_fInnerRadius2; // fInnerRadius^2 uniform float m_fKrESun; // Kr * ESun uniform float m_fKmESun; // Km * ESun uniform float m_fKr4PI; // Kr * 4 * PI uniform float m_fKm4PI; // Km * 4 * PI uniform float m_fScale; // 1 / (fOuterRadius - fInnerRadius) uniform float m_fScaleDepth; // The scale depth (i.e. the altitude at which the atmosphere's average density is found) uniform float m_fScaleOverScaleDepth; // fScale / fScaleDepth attribute vec4 inPosition; vec3 v3ELightPos = vec3(g_WorldMatrix * vec4(m_v3LightPos, 1.0)); vec3 v3ECameraPos= vec3(g_WorldMatrix * vec4(m_v3CameraPos, 1.0)); const int nSamples = 2; const float fSamples = 2.0; varying vec4 color; float scale(float fCos) { float x = 1.0 - fCos; return m_fScaleDepth * exp(-0.00287 + x*(0.459 + x*(3.83 + x*(-6.80 + x*5.25)))); } void main(void) { gl_Position = g_WorldViewProjectionMatrix * inPosition; // Get the ray from the camera to the vertex and its length (which is the far point of the ray passing through the atmosphere) vec3 v3Pos = vec3(g_WorldMatrix * inPosition); vec3 v3Ray = v3Pos - v3ECameraPos; float fFar = length(v3Ray); v3Ray /= fFar; // Calculate the closest intersection of the ray with the outer atmosphere (which is the near point of the ray passing through the atmosphere) float B = 2.0 * dot(m_v3CameraPos, v3Ray); float C = m_fCameraHeight2 - m_fOuterRadius2; float fDet = max(0.0, B*B - 4.0 * C); float fNear = 0.5 * (-B - sqrt(fDet)); // Calculate the ray's starting position, then calculate its scattering offset vec3 v3Start = m_v3CameraPos + v3Ray * fNear; fFar -= fNear; float fDepth = exp((m_fInnerRadius - m_fOuterRadius) / m_fScaleDepth); float fCameraAngle = dot(-v3Ray, v3Pos) / fFar; float fLightAngle = dot(v3ELightPos, v3Pos) / fFar; float fCameraScale = scale(fCameraAngle); float fLightScale = scale(fLightAngle); float fCameraOffset = fDepth*fCameraScale; float fTemp = (fLightScale + fCameraScale); // Initialize the scattering loop variables float fSampleLength = fFar / fSamples; float fScaledLength = fSampleLength * m_fScale; vec3 v3SampleRay = v3Ray * fSampleLength; vec3 v3SamplePoint = v3Start + v3SampleRay * 0.5; // Now loop through the sample rays vec3 v3FrontColor = vec3(0.0, 0.0, 0.0); vec3 v3Attenuate; for(int i=0; i<nSamples; i++) { float fHeight = length(v3SamplePoint); float fDepth = exp(m_fScaleOverScaleDepth * (m_fInnerRadius - fHeight)); float fScatter = fDepth*fTemp - fCameraOffset; v3Attenuate = exp(-fScatter * (m_v3InvWavelength * m_fKr4PI + m_fKm4PI)); v3FrontColor += v3Attenuate * (fDepth * fScaledLength); v3SamplePoint += v3SampleRay; } vec3 first = v3FrontColor * (m_v3InvWavelength * m_fKrESun + m_fKmESun); vec3 secondary = v3Attenuate; color = vec4((first + vec3(0.25,0.25,0.25) * secondary), 1.0); // ^^ that color is passed to the frag shader and is used as the gl_FragColor } Here is also an image of the problem image

  Read the article

• Normal maps red in OpenGL?

  - by KaiserJohaan

  I am using Assimp to import 3d models, and FreeImage to parse textures. The problem I am having is that the normal maps are actually red rather than blue when I try to render them as normal diffuse textures. http://i42.tinypic.com/289ing3.png When I open the images in a image-viewing program they do indeed show up as blue. Heres when I create the texture; OpenGLTexture::OpenGLTexture(const std::vector<uint8_t>& textureData, uint32_t textureWidth, uint32_t textureHeight, TextureType textureType, Logger& logger) : mLogger(logger), mTextureID(gNextTextureID++), mTextureType(textureType) { glGenTextures(1, &mTexture); CHECK_GL_ERROR(mLogger); glBindTexture(GL_TEXTURE_2D, mTexture); CHECK_GL_ERROR(mLogger); glTexImage2D(GL_TEXTURE_2D, 0, GL_RGBA, textureWidth, textureHeight, 0, glTextureFormat, GL_UNSIGNED_BYTE, &textureData[0]); CHECK_GL_ERROR(mLogger); glGenerateMipmap(GL_TEXTURE_2D); CHECK_GL_ERROR(mLogger); glBindTexture(GL_TEXTURE_2D, 0); CHECK_GL_ERROR(mLogger); } Here is my fragment shader. You can see I just commented out the normal-map parsing and treated the normal map texture as the diffuse texture to display it and illustrate the problem. As for the rest of the code it interacts as expected with the diffuse textures so I dont see a obvious problem there. "#version 330 \n \ \n \ layout(std140) uniform; \n \ \n \ const int MAX_LIGHTS = 8; \n \ \n \ struct Light \n \ { \n \ vec4 mLightColor; \n \ vec4 mLightPosition; \n \ vec4 mLightDirection; \n \ \n \ int mLightType; \n \ float mLightIntensity; \n \ float mLightRadius; \n \ float mMaxDistance; \n \ }; \n \ \n \ uniform UnifLighting \n \ { \n \ vec4 mGamma; \n \ vec3 mViewDirection; \n \ int mNumLights; \n \ \n \ Light mLights[MAX_LIGHTS]; \n \ } Lighting; \n \ \n \ uniform UnifMaterial \n \ { \n \ vec4 mDiffuseColor; \n \ vec4 mAmbientColor; \n \ vec4 mSpecularColor; \n \ vec4 mEmissiveColor; \n \ \n \ bool mHasDiffuseTexture; \n \ bool mHasNormalTexture; \n \ bool mLightingEnabled; \n \ float mSpecularShininess; \n \ } Material; \n \ \n \ uniform sampler2D unifDiffuseTexture; \n \ uniform sampler2D unifNormalTexture; \n \ \n \ in vec3 frag_position; \n \ in vec3 frag_normal; \n \ in vec2 frag_texcoord; \n \ in vec3 frag_tangent; \n \ in vec3 frag_bitangent; \n \ \n \ out vec4 finalColor; " " \n \ \n \ void CalcGaussianSpecular(in vec3 dirToLight, in vec3 normal, out float gaussianTerm) \n \ { \n \ vec3 viewDirection = normalize(Lighting.mViewDirection); \n \ vec3 halfAngle = normalize(dirToLight + viewDirection); \n \ \n \ float angleNormalHalf = acos(dot(halfAngle, normalize(normal))); \n \ float exponent = angleNormalHalf / Material.mSpecularShininess; \n \ exponent = -(exponent * exponent); \n \ \n \ gaussianTerm = exp(exponent); \n \ } \n \ \n \ vec4 CalculateLighting(in Light light, in vec4 diffuseTexture, in vec3 normal) \n \ { \n \ if (light.mLightType == 1) // point light \n \ { \n \ vec3 positionDiff = light.mLightPosition.xyz - frag_position; \n \ float dist = max(length(positionDiff) - light.mLightRadius, 0); \n \ \n \ float attenuation = 1 / ((dist/light.mLightRadius + 1) * (dist/light.mLightRadius + 1)); \n \ attenuation = max((attenuation - light.mMaxDistance) / (1 - light.mMaxDistance), 0); \n \ \n \ vec3 dirToLight = normalize(positionDiff); \n \ float angleNormal = clamp(dot(normalize(normal), dirToLight), 0, 1); \n \ \n \ float gaussianTerm = 0.0; \n \ if (angleNormal > 0.0) \n \ CalcGaussianSpecular(dirToLight, normal, gaussianTerm); \n \ \n \ return diffuseTexture * (attenuation * angleNormal * Material.mDiffuseColor * light.mLightIntensity * light.mLightColor) + \n \ (attenuation * gaussianTerm * Material.mSpecularColor * light.mLightIntensity * light.mLightColor); \n \ } \n \ else if (light.mLightType == 2) // directional light \n \ { \n \ vec3 dirToLight = normalize(light.mLightDirection.xyz); \n \ float angleNormal = clamp(dot(normalize(normal), dirToLight), 0, 1); \n \ \n \ float gaussianTerm = 0.0; \n \ if (angleNormal > 0.0) \n \ CalcGaussianSpecular(dirToLight, normal, gaussianTerm); \n \ \n \ return diffuseTexture * (angleNormal * Material.mDiffuseColor * light.mLightIntensity * light.mLightColor) + \n \ (gaussianTerm * Material.mSpecularColor * light.mLightIntensity * light.mLightColor); \n \ } \n \ else if (light.mLightType == 4) // ambient light \n \ return diffuseTexture * Material.mAmbientColor * light.mLightIntensity * light.mLightColor; \n \ else \n \ return vec4(0.0); \n \ } \n \ \n \ void main() \n \ { \n \ vec4 diffuseTexture = vec4(1.0); \n \ if (Material.mHasDiffuseTexture) \n \ diffuseTexture = texture(unifDiffuseTexture, frag_texcoord); \n \ \n \ vec3 normal = frag_normal; \n \ if (Material.mHasNormalTexture) \n \ { \n \ diffuseTexture = vec4(normalize(texture(unifNormalTexture, frag_texcoord).xyz * 2.0 - 1.0), 1.0); \n \ // vec3 normalTangentSpace = normalize(texture(unifNormalTexture, frag_texcoord).xyz * 2.0 - 1.0); \n \ //mat3 tangentToWorldSpace = mat3(normalize(frag_tangent), normalize(frag_bitangent), normalize(frag_normal)); \n \ \n \ // normal = tangentToWorldSpace * normalTangentSpace; \n \ } \n \ \n \ if (Material.mLightingEnabled) \n \ { \n \ vec4 accumLighting = vec4(0.0); \n \ \n \ for (int lightIndex = 0; lightIndex < Lighting.mNumLights; lightIndex++) \n \ accumLighting += Material.mEmissiveColor * diffuseTexture + \n \ CalculateLighting(Lighting.mLights[lightIndex], diffuseTexture, normal); \n \ \n \ finalColor = pow(accumLighting, Lighting.mGamma); \n \ } \n \ else { \n \ finalColor = pow(diffuseTexture, Lighting.mGamma); \n \ } \n \ } \n"; Why is this? does normal-map textures need some sort of special treatment in opengl?

  Read the article

• SDK for MediaTek

  - by Carlos Paz

  How can we get (paying) the SDK for MediaTek 6223/6225/6235? Regards, Carlos Paz lorgot at hotmail dot com

  Read the article

• Angle between two 2d vectors, diff between two methods?

  - by Sean Ochoa

  Hey all. I've got this code snippet, and I'm wondering why the results of the first method differ from the results of the second method, given the same input? public double AngleBetween_1(vector a, vector b) { var dotProd = a.Dot(b); var lenProd = a.Len*b.Len; var divOperation = dotProd/lenProd; return Math.Acos(divOperation) * (180.0 / Math.PI); } public double AngleBetween_2(vector a, vector b) { var dotProd = a.Dot(b); var lenProd = a.Len*b.Len; var divOperation = dotProd/lenProd; return (1/Math.Cos(divOperation)) * (180.0 / Math.PI); }

  Read the article

• Switch to tab by typing a substring of its name in Visual Studio 2005

  - by Vineus

  Is there a way to navigate between tabs in VS similar to the emacs iswtichb-mode or Firefox ubiquity switch tab mode (https://wiki.mozilla.org/Labs/Ubiquity/Ubiquity_0.1_Author_Tutorial#Switching_Tabs) ? In these apps, you just type a substring of the title of the tab (or buffer for emacs) to switch to this tab. For instance, to switch to a tab named "App_Code/Data/MyProgram.cs", you just invoke the tab switching command and then type "Progr" for instance to list all the tab whose name matches this string, including "MyProgram.cs". It's much easier to switch between tabs this way when you have a lot of documents open and when you now where to go (which is the case in most situation) Thank you !

  Read the article

• ASP Login page for ASP.NET Application

  - by The King

  Hi All, In my work place, we have several classic ASP and ASP.NET application. All these application though doing different works are integrated through a single sign on mode, which is handled by one main application. The main application is in classic ASP and verifies the userid and password initially and then stores the UserID in a session variable, which is then used by all other ASP and ASP.NET page as a valid Authenticated user. (For DOT NET pages we use session bridging) Is this how authentication is done is classic ASP? (I dont know classic ASP much) From the time I was introduced to this setup, I started to worry whether this setup is flawless? Is there any better way to handle the same ? Will it be possible to authenticate for both classic asp and DOT NET in the same login page? Thanks in advance for you answer Raja

  Read the article

• ansi-c fscanf problem

  - by mongoose

  hi i read the file as follows fscanf(fp,"%f %f %f",&*(p1+i), &*(p2+i), &*(p3+i)); my file's lines consists of three floating point numbers... the problem i have is that in the file let's say i have some floating points with let's say maximum of two digits after the dot. but when i ask c to print those values using different formatting, for example %lf,%.2lf,%.4lf... it starts to play with the digits... my only concern is this, if i have let's say 1343.23 in the file, then will c use this value exactly as it is in computations or it will play with the digits after the dot. if it will play, then how is it possible to make it so that it uses floating point numbers exactly as they are? for example in last case even if i ask it to print that value using %.10lf i would expect it to print only 1343.2300000000.? thanks a lot!

  Read the article

• DateTime: Require the user to enter a time component

  - by Heinzi

  Checking if a user input is a valid date or a valid "date + time" is easy: .NET provides DateTime.TryParse (and, in addition, VB.NET provides IsDate). Now, I want to check if the user entered a date including a time component. So, when using a German locale, 31.12.2010 00:00 should be OK, but 31.12.2010 shouldn't. I know I could use DateTime.TryParseExact like this: Dim formats() As String = {"d.M.yyyy H:mm:ss", "dd.M.yyyy H:mm:ss", _ "d.MM.yyyy H:mm:ss", "d.MM.yyyy H:mm:ss", _ "d.M.yyyy H:mm", ...} Dim result = DateTime.TryParseExact(userInput, formats, _ Globalization.CultureInfo.CurrentCulture, ..., result) but then I would hard-code the German format of specifying dates (day dot month dot year), which is considered bad practice and will make trouble should we ever want to localize our application. In addition, formats would be quite a large list of all possible combinations (one digit, two digits, ...). Is there a more elegant solution?

  Read the article

• LINQ to SQL vs Entity Framework for an app with a future SQL Azure version

  - by Craig L

  I've got a vertical market Dot Net Framework 1.1 C#/WinForms/SQL Server 2000 application. Currently it uses ADO.Net and Microsoft's SQLHelper for CRUD operations. I've successfully converted it to Dot Net Framework 4 C#/WinForms/ SQL Server 2008. What I'd like to do is also offer my customers the ability to use SQL Azure as a backend storage for their data instead of local/LAN SQL Server. If I know SQL Azure is in my application's future, should I: A. Switch to LINQ to SQL B. Swith to Entity Framework C. Stick with ADO.Net and SQLHelper Thanks !

  Read the article

• Inline & not-inline

  - by anon

  Suppose I have: struct Vec3 { double x; double y; double z; } ; inline double dot(const Vec3& lhs, const Vec3& rhs) { return lhs.x * rhs.x + lhs.y * rhs.y + lhs.z * rhs.z ; } Is it possible to have "dot" also exist in a non-inlined version, so that it can be in the *.so , so that when I dl open it I can call it? I.e. I want files that include the above header to use the inlined version, but I also want the function to exist in a *.so, so I can dl open it and call it dynamically.

  Read the article

• What's the best way to do literate programming in Python on Windows?

  - by JasonFruit

  I've been playing with various ways of doing literate programming in Python. I like noweb, but I have two main problems with it: first, it is hard to build on Windows, where I spend about half my development time; and second, it requires me to indent each chunk of code as it will be in the final program --- which I don't necessarily know when I write it. I don't want to use Leo, because I'm very attached to Emacs. Is there a good literate programming tool that: Runs on Windows Allows me to set the indentation of the chunks when they're used, not when they're written Still lets me work in Emacs Thanks! Correction: noweb does allow me to indent later --- I misread the paper I found on it. By default, notangle preserves whitespace and maintains indentation when expanding chunks. It can therefore be used with languages like Miranda and Haskell, in which indentation is significant That leaves me with only the "Runs on Windows" problem.

  Read the article

• Why is numpy's einsum faster than numpy's built in functions?

  - by Ophion

  Lets start with three arrays of dtype=np.double. Timings are performed on a intel CPU using numpy 1.7.1 compiled with icc and linked to intel's mkl. A AMD cpu with numpy 1.6.1 compiled with gcc without mkl was also used to verify the timings. Please note the timings scale nearly linearly with system size and are not due to the small overhead incurred in the numpy functions if statements these difference will show up in microseconds not milliseconds: arr_1D=np.arange(500,dtype=np.double) large_arr_1D=np.arange(100000,dtype=np.double) arr_2D=np.arange(500**2,dtype=np.double).reshape(500,500) arr_3D=np.arange(500**3,dtype=np.double).reshape(500,500,500) First lets look at the np.sum function: np.all(np.sum(arr_3D)==np.einsum('ijk->',arr_3D)) True %timeit np.sum(arr_3D) 10 loops, best of 3: 142 ms per loop %timeit np.einsum('ijk->', arr_3D) 10 loops, best of 3: 70.2 ms per loop Powers: np.allclose(arr_3D*arr_3D*arr_3D,np.einsum('ijk,ijk,ijk->ijk',arr_3D,arr_3D,arr_3D)) True %timeit arr_3D*arr_3D*arr_3D 1 loops, best of 3: 1.32 s per loop %timeit np.einsum('ijk,ijk,ijk->ijk', arr_3D, arr_3D, arr_3D) 1 loops, best of 3: 694 ms per loop Outer product: np.all(np.outer(arr_1D,arr_1D)==np.einsum('i,k->ik',arr_1D,arr_1D)) True %timeit np.outer(arr_1D, arr_1D) 1000 loops, best of 3: 411 us per loop %timeit np.einsum('i,k->ik', arr_1D, arr_1D) 1000 loops, best of 3: 245 us per loop All of the above are twice as fast with np.einsum. These should be apples to apples comparisons as everything is specifically of dtype=np.double. I would expect the speed up in an operation like this: np.allclose(np.sum(arr_2D*arr_3D),np.einsum('ij,oij->',arr_2D,arr_3D)) True %timeit np.sum(arr_2D*arr_3D) 1 loops, best of 3: 813 ms per loop %timeit np.einsum('ij,oij->', arr_2D, arr_3D) 10 loops, best of 3: 85.1 ms per loop Einsum seems to be at least twice as fast for np.inner, np.outer, np.kron, and np.sum regardless of axes selection. The primary exception being np.dot as it calls DGEMM from a BLAS library. So why is np.einsum faster that other numpy functions that are equivalent? The DGEMM case for completeness: np.allclose(np.dot(arr_2D,arr_2D),np.einsum('ij,jk',arr_2D,arr_2D)) True %timeit np.einsum('ij,jk',arr_2D,arr_2D) 10 loops, best of 3: 56.1 ms per loop %timeit np.dot(arr_2D,arr_2D) 100 loops, best of 3: 5.17 ms per loop The leading theory is from @sebergs comment that np.einsum can make use of SSE2, but numpy's ufuncs will not until numpy 1.8 (see the change log). I believe this is the correct answer, but have not been able to confirm it. Some limited proof can be found by changing the dtype of input array and observing speed difference and the fact that not everyone observes the same trends in timings.

  Read the article

• Open a document from library Word opened but the contents is not loaded

  - by user300440

  [Environment] Server Sharepoint Portal Server 2003 Client Windows XP Internet Explorer 6.0 Microsoft Office 2003 Hello~ Today I received a call from one of my client and she said that she received an alert, "Ambiguous name detected: tempDDE" when attemping to open a doc from library. So I googled some and found solutions from MS and others and modified from Normal.dot to Normal1.dot. But after that, when I opened it again from library another problem happend and it is the doc contents is not loaded. When I click the link of doc, then the WIN?WORD.exe pops up but the contents of the document is not showing up (Silent). I tried some Open the doc file using Word Open Menu (Library Link) = Worked Get the url of the file and open it uing using Word Open Menu = Worked Add the url to Trusted Site = Done but not helped Any advices are welcomed. Thanks, Karl

  Read the article

• No norwegian characters in LaTeX

  - by DreamCodeR

  Hi, I have translated a document from English to Norwegian in the LaTeX format, and while using norwegian special characters, I get an error using \usepackage[utf8x]{inputenc} to try and display the norwegian (scandinavian) special characters in PostScript/PDF/DVI format, saying Package utf8x Error: MalformedUTF-8sequence. So while that didn't work, I tried out another possible solution: \usepackage{ucs} \usepackage[norsk]babel And when I tried to save that in Emacs I get this message: These default coding systems were tried to encode text in the buffer `lol.tex': (utf-8-unix (905 . 4194277) (916 . 4194245) (945 . 4194278) (950 . 4194277) (954 . 4194296) (990 . 4194277) (1010 . 4194277) (1013 . 4194278) (1051 . 4194277) (1078 . 4194296) (1105 . 4194296)) However, each of them encountered characters it couldn't encode: utf-8-unix cannot encode these: \345 \305 \346 \345 \370 \345 \345 \346 \345 \370 ... Thanks to Emacs I have the possibility to check out the properties of those characters and the first one tells me: character: \345 (4194277, #o17777745, #x3fffe5) preferred charset: eight-bit (Raw bytes 128-255) code point: 0xE5 syntax: w which means: word buffer code: #xE5 file code: not encodable by coding system utf-8-unix display: not encodable for terminal Which doesn't tell me much. When I try to build this with texi2dvi --dvipdf filename.text I get a perfectly fine PDF, all without the special norwegian characters. When I am about to save Emacs also ask me: "Select coding system (default raw-text):" And I type in utf-8 to choose its coding system. I have also tried to choose default raw-text to see if I get some different result. But nothing. At last I tried \lstset{inputencoding=utf8x, extendedchars=\true} ... a code I came over while trying to google the solution to this problem. Which gives me this error: Undefined control sequence. So basically, I have tried every encoding option I have been able to find and nothing works. I am desperately trying to make this work since the norwegian translation must be published before the deadline. As an additional information I may add that I found out later on that I only had the en_US.UTF-8 in my locale, so I added nb_NO.UTF-8 and nb_NO.ISO-8859-15 and ran locale-gen + reboot without any changes. I hope I provided enough information to get some assistance, the characters in question is æ ø å.

  Read the article

• C# - Angle between two 2d vectors, diff between two methods?

  - by Sean Ochoa

  Hey all. I've got this code snippet, and I'm wondering why the results of the first method differ from the results of the second method, given the same input? public double AngleBetween_1(vector a, vector b) { var dotProd = a.Dot(b); var lenProd = Len*b.Len; var divOperation = dotProd/lenProd; return Math.Acos(divOperation) * (180.0 / Math.PI); } public double AngleBetween_2(vector a, vector b) { var dotProd = a.Dot(b); var lenProd = Len*b.Len; var divOperation = dotProd/lenProd; return (1/Math.Cos(divOperation)) * (180.0 / Math.PI); }

  Read the article

• Need a HackHound.org invite

  - by Kovu

  Hi, it's very urgent: Anyone have a HackHound.org Invite for me? EMail is hh(at)repair-your-iphone(dot)de

  Read the article

• Problem implementing Blinn–Phong shading model

  - by Joe Hopfgartner

  I did this very simple, perfectly working, implementation of Phong Relflection Model (There is no ambience implemented yet, but that doesn't bother me for now). The functions should be self explaining. /** * Implements the classic Phong illumination Model using a reflected light * vector. */ public class PhongIllumination implements IlluminationModel { @RGBParam(r = 0, g = 0, b = 0) public Vec3 ambient; @RGBParam(r = 1, g = 1, b = 1) public Vec3 diffuse; @RGBParam(r = 1, g = 1, b = 1) public Vec3 specular; @FloatParam(value = 20, min = 1, max = 200.0f) public float shininess; /* * Calculate the intensity of light reflected to the viewer . * * @param P = The surface position expressed in world coordinates. * * @param V = Normalized viewing vector from surface to eye in world * coordinates. * * @param N = Normalized normal vector at surface point in world * coordinates. * * @param surfaceColor = surfaceColor Color of the surface at the current * position. * * @param lights = The active light sources in the scene. * * @return Reflected light intensity I. */ public Vec3 shade(Vec3 P, Vec3 V, Vec3 N, Vec3 surfaceColor, Light lights[]) { Vec3 surfaceColordiffused = Vec3.mul(surfaceColor, diffuse); Vec3 totalintensity = new Vec3(0, 0, 0); for (int i = 0; i < lights.length; i++) { Vec3 L = lights[i].calcDirection(P); N = N.normalize(); V = V.normalize(); Vec3 R = Vec3.reflect(L, N); // reflection vector float diffuseLight = Vec3.dot(N, L); float specularLight = Vec3.dot(V, R); if (diffuseLight > 0) { totalintensity = Vec3.add(Vec3.mul(Vec3.mul( surfaceColordiffused, lights[i].calcIntensity(P)), diffuseLight), totalintensity); if (specularLight > 0) { Vec3 Il = lights[i].calcIntensity(P); Vec3 Ilincident = Vec3.mul(Il, Math.max(0.0f, Vec3 .dot(N, L))); Vec3 intensity = Vec3.mul(Vec3.mul(specular, Ilincident), (float) Math.pow(specularLight, shininess)); totalintensity = Vec3.add(totalintensity, intensity); } } } return totalintensity; } } Now i need to adapt it to become a Blinn-Phong illumination model I used the formulas from hearn and baker, followed pseudocodes and tried to implement it multiple times according to wikipedia articles in several languages but it never worked. I just get no specular reflections or they are so weak and/or are at the wrong place and/or have the wrong color. From the numerous wrong implementations I post some little code that already seems to be wrong. So I calculate my Half Way vector and my new specular light like so: Vec3 H = Vec3.mul(Vec3.add(L.normalize(), V), Vec3.add(L.normalize(), V).length()); float specularLight = Vec3.dot(H, N); With theese little changes it should already work (maby not with correct intensity but basically it should be correct). But the result is wrong. Here are two images. Left how it should render correctly and right how it renders. If i lower the shininess factor you can see a little specular light at the top right: Altough I understand the concept of Phong illumination and also the simplified more performant adaptaion of blinn phong I am trying around for days and just cant get it to work. Any help is appriciated. Edit: I was made aware of an error by this answer, that i am mutiplying by |L+V| instead of dividing by it when calculating H. I changed to deviding doing so: Vec3 H = Vec3.mul(Vec3.add(L.normalize(), V), 1/Vec3.add(L.normalize(), V).length()); Unfortunately this doesnt change much. The results look like this: and if I rise the specular constant and lower the shininess You can see the effects more clearly in a smilar wrong way: However this division just the normalisation. I think I am missing one step. Because the formulas like this just dont make sense to me. If you look at this picture: http://en.wikipedia.org/wiki/File:Blinn-Phong_vectors.svg The projection of H to N is far less than V to R. And if you imagine changing the vector V in the picture the angle is the same when the viewing vector is "on the left side". and becomes more and more different when going to the right. I pesonally would multiply the whole projection by two to become something similiar (and the hole point is to avoid the calculation of R). Altough I didnt read anythinga bout that anywehre i am gonna try this out... Result: The intension of the specular light is far too much (white areas) and the position is still wrong. I think I am messing something else up because teh reflection are just at the wrong place. But what? Edit: Now I read on wikipedia in the notes that the angle of N/H is in fact approximalty half or V/R. To compensate that i should multiply my shineness exponent by 4 rather than my projection. If i do that I end up with this: Far to intense but still one thing. The projection is at the wrong place. Where could i mess up my vectors?

  Read the article

< Previous Page | 43 44 45 46 47 48 49 50 51 52 53 54  | Next Page >