Search Results

Search found 9387 results on 376 pages for 'double byte'.

Page 23/376 | < Previous Page | 19 20 21 22 23 24 25 26 27 28 29 30  | Next Page >

  • Unable to read data from the transport connection: An existing connection was forcibly closed by the remote host

    - by Paul J. Warner
    I am having an issue with a program where after 6 mins +- 5 secs we get the above exception. Some more info about the exception stacktrace is below. This all happens pretty religiously, 6 mins goes by and bam the following 3 exeptions. We have the application installed in 2 other environments and it is working fine there. I am hoping to find some server settings either IIS 6 or Server 2003 settings that may be causing this issue to occur. I have reviewed some of the similar questions and don't see very many answers. I am hoping that maybe the information I have provided may help a little bit. 208741,Exception,,,,2011-06-21 00:30:14.193,SERVERNAME,2624,1,CLIENTNAME,The underlying connection was closed: An unexpected error occurred on a receive. , at System.Web.Services.Protocols.WebClientProtocol.GetWebResponse(WebRequest request) at System.Web.Services.Protocols.HttpWebClientProtocol.GetWebResponse(WebRequest request) at Microsoft.Web.Services3.WebServicesClientProtocol.GetResponse(WebRequest request, IAsyncResult result) at System.Web.Services.Protocols.SoapHttpClientProtocol.Invoke(String methodName, Object[] parameters) at System.Net.Sockets.NetworkStream.Read(Byte[] buffer, Int32 offset, Int32 size) at System.Net.FixedSizeReader.ReadPacket(Byte[] buffer, Int32 offset, Int32 count) at System.Net.Security._SslStream.StartFrameHeader(Byte[] buffer, Int32 offset, Int32 count, AsyncProtocolRequest asyncRequest) at System.Net.Security._SslStream.StartReading(Byte[] buffer, Int32 offset, Int32 count, AsyncProtocolRequest asyncRequest) at System.Net.Security._SslStream.ProcessRead(Byte[] buffer, Int32 offset, Int32 count, AsyncProtocolRequest asyncRequest) at System.Net.TlsStream.Read(Byte[] buffer, Int32 offset, Int32 size) at System.Net.PooledStream.Read(Byte[] buffer, Int32 offset, Int32 size) at System.Net.Connection.SyncRead(HttpWebRequest request, Boolean userRetrievedStream, Boolean probeRead),2004437127,114,1 208742,Exception,,,,2011-06-21 00:30:14.227,SERVERNAME,2624,1,CLIENTNAME,Unable to read data from the transport connection: An existing connection was forcibly closed by the remote host. , at System.Net.Sockets.NetworkStream.Read(Byte[] buffer, Int32 offset, Int32 size) at System.Net.FixedSizeReader.ReadPacket(Byte[] buffer, Int32 offset, Int32 count) at System.Net.Security._SslStream.StartFrameHeader(Byte[] buffer, Int32 offset, Int32 count, AsyncProtocolRequest asyncRequest) at System.Net.Security._SslStream.StartReading(Byte[] buffer, Int32 offset, Int32 count, AsyncProtocolRequest asyncRequest) at System.Net.Security._SslStream.ProcessRead(Byte[] buffer, Int32 offset, Int32 count, AsyncProtocolRequest asyncRequest) at System.Net.TlsStream.Read(Byte[] buffer, Int32 offset, Int32 size) at System.Net.PooledStream.Read(Byte[] buffer, Int32 offset, Int32 size) at System.Net.Connection.SyncRead(HttpWebRequest request, Boolean userRetrievedStream, Boolean probeRead),2004437127,114,1 208743,Exception,,,,2011-06-21 00:30:14.287,SERVERNAME,2624,1,CLIENTNAME,An existing connection was forcibly closed by the remote host , at System.Net.Sockets.NetworkStream.Read(Byte[] buffer, Int32 offset, Int32 size),-691097507,62,1

    Read the article

  • Unable to read data from the transport connection: An existing connection was forcibly closed by the remote host.

    - by Paul J. Warner
    I am having an issue with a program where after 6 mins +- 5 secs we get the above exception. Some more info about the exception stacktrace is below. This all happens pretty religiously, 6 mins goes by and bam the following 3 exeptions. We have the application installed in 2 other environments and it is working fine there. I am hoping to find some server settings either IIS 6 or Server 2003 settings that may be causing this issue to occur. I have reviewed some of the similar questions and don't see very many answers. I am hoping that maybe the information I have provided may help a little bit. 208741,Exception,,,,2011-06-21 00:30:14.193,SERVERNAME,2624,1,CLIENTNAME,The underlying connection was closed: An unexpected error occurred on a receive. , at System.Web.Services.Protocols.WebClientProtocol.GetWebResponse(WebRequest request) at System.Web.Services.Protocols.HttpWebClientProtocol.GetWebResponse(WebRequest request) at Microsoft.Web.Services3.WebServicesClientProtocol.GetResponse(WebRequest request, IAsyncResult result) at System.Web.Services.Protocols.SoapHttpClientProtocol.Invoke(String methodName, Object[] parameters) at System.Net.Sockets.NetworkStream.Read(Byte[] buffer, Int32 offset, Int32 size) at System.Net.FixedSizeReader.ReadPacket(Byte[] buffer, Int32 offset, Int32 count) at System.Net.Security._SslStream.StartFrameHeader(Byte[] buffer, Int32 offset, Int32 count, AsyncProtocolRequest asyncRequest) at System.Net.Security._SslStream.StartReading(Byte[] buffer, Int32 offset, Int32 count, AsyncProtocolRequest asyncRequest) at System.Net.Security._SslStream.ProcessRead(Byte[] buffer, Int32 offset, Int32 count, AsyncProtocolRequest asyncRequest) at System.Net.TlsStream.Read(Byte[] buffer, Int32 offset, Int32 size) at System.Net.PooledStream.Read(Byte[] buffer, Int32 offset, Int32 size) at System.Net.Connection.SyncRead(HttpWebRequest request, Boolean userRetrievedStream, Boolean probeRead),2004437127,114,1 208742,Exception,,,,2011-06-21 00:30:14.227,SERVERNAME,2624,1,CLIENTNAME,Unable to read data from the transport connection: An existing connection was forcibly closed by the remote host. , at System.Net.Sockets.NetworkStream.Read(Byte[] buffer, Int32 offset, Int32 size) at System.Net.FixedSizeReader.ReadPacket(Byte[] buffer, Int32 offset, Int32 count) at System.Net.Security._SslStream.StartFrameHeader(Byte[] buffer, Int32 offset, Int32 count, AsyncProtocolRequest asyncRequest) at System.Net.Security._SslStream.StartReading(Byte[] buffer, Int32 offset, Int32 count, AsyncProtocolRequest asyncRequest) at System.Net.Security._SslStream.ProcessRead(Byte[] buffer, Int32 offset, Int32 count, AsyncProtocolRequest asyncRequest) at System.Net.TlsStream.Read(Byte[] buffer, Int32 offset, Int32 size) at System.Net.PooledStream.Read(Byte[] buffer, Int32 offset, Int32 size) at System.Net.Connection.SyncRead(HttpWebRequest request, Boolean userRetrievedStream, Boolean probeRead),2004437127,114,1 208743,Exception,,,,2011-06-21 00:30:14.287,SERVERNAME,2624,1,CLIENTNAME,An existing connection was forcibly closed by the remote host , at System.Net.Sockets.NetworkStream.Read(Byte[] buffer, Int32 offset, Int32 size),-691097507,62,1

    Read the article

  • What is the fastest (possibly unsafe) way to read a byte[]?

    - by Aidiakapi
    I'm working on a server project in C#, and after a TCP message is received, it is parsed, and stored in a byte[] of exact size. (Not a buffer of fixed length, but a byte[] of an absolute length in which all data is stored.) Now for reading this byte[] I'll be creating some wrapper functions (also for compatibility), these are the signatures of all functions I need: public byte ReadByte(); public sbyte ReadSByte(); public short ReadShort(); public ushort ReadUShort(); public int ReadInt(); public uint ReadUInt(); public float ReadFloat(); public double ReadDouble(); public string ReadChars(int length); public string ReadString(); The string is a \0 terminated string, and is probably encoded in ASCII or UTF-8, but I cannot tell that for sure, since I'm not writing the client. The data exists of: byte[] _data; int _offset; Now I can write all those functions manually, like this: public byte ReadByte() { return _data[_offset++]; } public sbyte ReadSByte() { byte r = _data[_offset++]; if (r >= 128) return (sbyte)(r - 256); else return (sbyte)r; } public short ReadShort() { byte b1 = _data[_offset++]; byte b2 = _data[_offset++]; if (b1 >= 128) return (short)(b1 * 256 + b2 - 65536); else return (short)(b1 * 256 + b2); } public short ReadUShort() { byte b1 = _data[_offset++]; return (short)(b1 * 256 + _data[_offset++]); } But I wonder if there's a faster way, not excluding the use of unsafe code, since this seems a little bit too much work for simple processing.

    Read the article

  • Processing Kinect v2 Color Streams in Parallel

    - by Chris Gardner
    Originally posted on: http://geekswithblogs.net/freestylecoding/archive/2014/08/20/processing-kinect-v2-color-streams-in-parallel.aspxProcessing Kinect v2 Color Streams in Parallel I've really been enjoying being a part of the Kinect for Windows Developer's Preview. The new hardware has some really impressive capabilities. However, with great power comes great system specs. Unfortunately, my little laptop that could is not 100% up to the task; I've had to get a little creative. The most disappointing thing I've run into is that I can't always cleanly display the color camera stream in managed code. I managed to strip the code down to what I believe is the bear minimum: using( ColorFrame _ColorFrame = e.FrameReference.AcquireFrame() ) { if( null == _ColorFrame ) return;   BitmapToDisplay.Lock(); _ColorFrame.CopyConvertedFrameDataToIntPtr( BitmapToDisplay.BackBuffer, Convert.ToUInt32( BitmapToDisplay.BackBufferStride * BitmapToDisplay.PixelHeight ), ColorImageFormat.Bgra ); BitmapToDisplay.AddDirtyRect( new Int32Rect( 0, 0, _ColorFrame.FrameDescription.Width, _ColorFrame.FrameDescription.Height ) ); BitmapToDisplay.Unlock(); } With this snippet, I'm placing the converted Bgra32 color stream directly on the BackBuffer of the WriteableBitmap. This gives me pretty smooth playback, but I still get the occasional freeze for half a second. After a bit of profiling, I discovered there were a few problems. The first problem is the size of the buffer along with the conversion on the buffer. At this time, the raw image format of the data from the Kinect is Yuy2. This is great for direct video processing. It would be ideal if I had a WriteableVideo object in WPF. However, this is not the case. Further digging led me to the real problem. It appears that the SDK is converting the input serially. Let's think about this for a second. The color camera is a 1080p camera. As we should all know, this give us a native resolution of 1920 x 1080. This produces 2,073,600 pixels. Yuy2 uses 4 bytes per 2 pixel, for a buffer size of 4,147,200 bytes. Bgra32 uses 4 bytes per pixel, for a buffer size of 8,294,400 bytes. The SDK appears to be doing this on one thread. I started wondering if I chould do this better myself. I mean, I have 8 cores in my system. Why can't I use them all? The first problem is converting a Yuy2 frame into a Bgra32 frame. It is NOT trivial. I spent a day of research of just how to do this. In the end, I didn't even produce the best algorithm possible, but it did work. After I managed to get that to work, I knew my next step was the get the conversion operation off the UI Thread. This was a simple process of throwing the work into a Task. Of course, this meant I had to marshal the final write to the WriteableBitmap back to the UI thread. Finally, I needed to vectorize the operation so I could run it safely in parallel. This was, mercifully, not quite as hard as I thought it would be. I had my loop return an index to a pair of pixels. From there, I had to tell the loop to do everything for this pair of pixels. If you're wondering why I did it for pairs of pixels, look back above at the specification for the Yuy2 format. I won't go into full detail on why each 4 bytes contains 2 pixels of information, but rest assured that there is a reason why the format is described in that way. The first working attempt at this algorithm successfully turned my poor laptop into a space heater. I very quickly brought and maintained all 8 cores up to about 97% usage. That's when I remembered that obscure option in the Task Parallel Library where you could limit the amount of parallelism used. After a little trial and error, I discovered 4 parallel tasks was enough for most cases. This yielded the follow code: private byte ClipToByte( int p_ValueToClip ) { return Convert.ToByte( ( p_ValueToClip < byte.MinValue ) ? byte.MinValue : ( ( p_ValueToClip > byte.MaxValue ) ? byte.MaxValue : p_ValueToClip ) ); }   private void ColorFrameArrived( object sender, ColorFrameArrivedEventArgs e ) { if( null == e.FrameReference ) return;   // If you do not dispose of the frame, you never get another one... using( ColorFrame _ColorFrame = e.FrameReference.AcquireFrame() ) { if( null == _ColorFrame ) return;   byte[] _InputImage = new byte[_ColorFrame.FrameDescription.LengthInPixels * _ColorFrame.FrameDescription.BytesPerPixel]; byte[] _OutputImage = new byte[BitmapToDisplay.BackBufferStride * BitmapToDisplay.PixelHeight]; _ColorFrame.CopyRawFrameDataToArray( _InputImage );   Task.Factory.StartNew( () => { ParallelOptions _ParallelOptions = new ParallelOptions(); _ParallelOptions.MaxDegreeOfParallelism = 4;   Parallel.For( 0, Sensor.ColorFrameSource.FrameDescription.LengthInPixels / 2, _ParallelOptions, ( _Index ) => { // See http://msdn.microsoft.com/en-us/library/windows/desktop/dd206750(v=vs.85).aspx int _Y0 = _InputImage[( _Index << 2 ) + 0] - 16; int _U = _InputImage[( _Index << 2 ) + 1] - 128; int _Y1 = _InputImage[( _Index << 2 ) + 2] - 16; int _V = _InputImage[( _Index << 2 ) + 3] - 128;   byte _R = ClipToByte( ( 298 * _Y0 + 409 * _V + 128 ) >> 8 ); byte _G = ClipToByte( ( 298 * _Y0 - 100 * _U - 208 * _V + 128 ) >> 8 ); byte _B = ClipToByte( ( 298 * _Y0 + 516 * _U + 128 ) >> 8 );   _OutputImage[( _Index << 3 ) + 0] = _B; _OutputImage[( _Index << 3 ) + 1] = _G; _OutputImage[( _Index << 3 ) + 2] = _R; _OutputImage[( _Index << 3 ) + 3] = 0xFF; // A   _R = ClipToByte( ( 298 * _Y1 + 409 * _V + 128 ) >> 8 ); _G = ClipToByte( ( 298 * _Y1 - 100 * _U - 208 * _V + 128 ) >> 8 ); _B = ClipToByte( ( 298 * _Y1 + 516 * _U + 128 ) >> 8 );   _OutputImage[( _Index << 3 ) + 4] = _B; _OutputImage[( _Index << 3 ) + 5] = _G; _OutputImage[( _Index << 3 ) + 6] = _R; _OutputImage[( _Index << 3 ) + 7] = 0xFF; } );   Application.Current.Dispatcher.Invoke( () => { BitmapToDisplay.WritePixels( new Int32Rect( 0, 0, Sensor.ColorFrameSource.FrameDescription.Width, Sensor.ColorFrameSource.FrameDescription.Height ), _OutputImage, BitmapToDisplay.BackBufferStride, 0 ); } ); } ); } } This seemed to yield a results I wanted, but there was still the occasional stutter. This lead to what I realized was the second problem. There is a race condition between the UI Thread and me locking the WriteableBitmap so I can write the next frame. Again, I'm writing approximately 8MB to the back buffer. Then, I started thinking I could cheat. The Kinect is running at 30 frames per second. The WPF UI Thread runs at 60 frames per second. This made me not feel bad about exploiting the Composition Thread. I moved the bulk of the code from the FrameArrived handler into CompositionTarget.Rendering. Once I was in there, I polled from a frame, and rendered it if it existed. Since, in theory, I'm only killing the Composition Thread every other hit, I decided I was ok with this for cases where silky smooth video performance REALLY mattered. This ode looked like this: private byte ClipToByte( int p_ValueToClip ) { return Convert.ToByte( ( p_ValueToClip < byte.MinValue ) ? byte.MinValue : ( ( p_ValueToClip > byte.MaxValue ) ? byte.MaxValue : p_ValueToClip ) ); }   void CompositionTarget_Rendering( object sender, EventArgs e ) { using( ColorFrame _ColorFrame = FrameReader.AcquireLatestFrame() ) { if( null == _ColorFrame ) return;   byte[] _InputImage = new byte[_ColorFrame.FrameDescription.LengthInPixels * _ColorFrame.FrameDescription.BytesPerPixel]; byte[] _OutputImage = new byte[BitmapToDisplay.BackBufferStride * BitmapToDisplay.PixelHeight]; _ColorFrame.CopyRawFrameDataToArray( _InputImage );   ParallelOptions _ParallelOptions = new ParallelOptions(); _ParallelOptions.MaxDegreeOfParallelism = 4;   Parallel.For( 0, Sensor.ColorFrameSource.FrameDescription.LengthInPixels / 2, _ParallelOptions, ( _Index ) => { // See http://msdn.microsoft.com/en-us/library/windows/desktop/dd206750(v=vs.85).aspx int _Y0 = _InputImage[( _Index << 2 ) + 0] - 16; int _U = _InputImage[( _Index << 2 ) + 1] - 128; int _Y1 = _InputImage[( _Index << 2 ) + 2] - 16; int _V = _InputImage[( _Index << 2 ) + 3] - 128;   byte _R = ClipToByte( ( 298 * _Y0 + 409 * _V + 128 ) >> 8 ); byte _G = ClipToByte( ( 298 * _Y0 - 100 * _U - 208 * _V + 128 ) >> 8 ); byte _B = ClipToByte( ( 298 * _Y0 + 516 * _U + 128 ) >> 8 );   _OutputImage[( _Index << 3 ) + 0] = _B; _OutputImage[( _Index << 3 ) + 1] = _G; _OutputImage[( _Index << 3 ) + 2] = _R; _OutputImage[( _Index << 3 ) + 3] = 0xFF; // A   _R = ClipToByte( ( 298 * _Y1 + 409 * _V + 128 ) >> 8 ); _G = ClipToByte( ( 298 * _Y1 - 100 * _U - 208 * _V + 128 ) >> 8 ); _B = ClipToByte( ( 298 * _Y1 + 516 * _U + 128 ) >> 8 );   _OutputImage[( _Index << 3 ) + 4] = _B; _OutputImage[( _Index << 3 ) + 5] = _G; _OutputImage[( _Index << 3 ) + 6] = _R; _OutputImage[( _Index << 3 ) + 7] = 0xFF; } );   BitmapToDisplay.WritePixels( new Int32Rect( 0, 0, Sensor.ColorFrameSource.FrameDescription.Width, Sensor.ColorFrameSource.FrameDescription.Height ), _OutputImage, BitmapToDisplay.BackBufferStride, 0 ); } }

    Read the article

  • Sublime text 2 syntax highlighter?

    - by BigSack
    I have coded my first custom syntax highlighter for sublime text 2, but i don't know how to install it. It is based on notepad++ highlighter found here https://70995658-a-62cb3a1a-s-sites.googlegroups.com/site/lohanplus/files/smali_npp.xml?attachauth=ANoY7criVTO9bDmIGrXwhZLQ_oagJzKKJTlbNDGRzMDVpFkO5i0N6hk_rWptvoQC1tBlNqcqFDD5NutD_2vHZx1J7hcRLyg1jruSjebHIeKdS9x0JCNrsRivgs6DWNhDSXSohkP1ZApXw0iQ0MgqcXjdp7CkJJ6pY_k5Orny9TfK8UWn_HKFsmPcpp967NMPtUnd--ad-BImtkEi-fox2tjs7zc5LabkDQ%3D%3D&attredirects=0&d=1 <?xml version="1.0" encoding="UTF-8"?> <!DOCTYPE plist PUBLIC "-//Apple//DTD PLIST 1.0//EN" "http://www.apple.com/DTDs/PropertyList-1.0.dtd"> <plist version="1.0"> <dict> <key>fileTypes</key> <array> <string>smali</string> </array> <dict> <key>Word1</key> <string>add-double add-double/2addr add-float add-float/2addr add-int add-int/2addr add-int/lit16 add-int/lit8 add-long add-long/2addr aget aget-boolean aget-byte aget-char aget-object aget-short aget-wide and-int and-int/2addr and-int/lit16 and-int/lit8 and-long and-long/2addr aput aput-boolean aput-byte aput-char aput-object aput-short aput-wide array-length check-cast cmp-long cmpg-double cmpg-float cmpl-double cmpl-float const const-class const-string const-string-jumbo const-wide const-wide/16 const-wide/32 const-wide/high16 const/16 const/4 const/high16 div-double div-double/2addr div-float div-float/2addr div-int div-int/2addr div-int/lit16 div-int/lit8 div-long div-long/2addr double-to-float double-to-int double-to-long execute-inline fill-array-data filled-new-array filled-new-array/range float-to-double float-to-int float-to-long goto goto/16 goto/32 if-eq if-eqz if-ge if-gez if-gt if-gtz if-le if-lez if-lt if-ltz if-ne if-nez iget iget-boolean iget-byte iget-char iget-object iget-object-quick iget-quick iget-short iget-wide iget-wide-quick instance-of int-to-byte int-to-char int-to-double int-to-float int-to-long int-to-short invoke-direct invoke-direct-empty invoke-direct/range invoke-interface invoke-interface/range invoke-static invoke-static/range invoke-super invoke-super-quick invoke-super-quick/range invoke-super/range invoke-virtual invoke-virtual-quick invoke-virtual-quick/range invoke-virtual/range iput iput-boolean iput-byte iput-char iput-object iput-object-quick iput-quick iput-short iput-wide iput-wide-quick long-to-double long-to-float long-to-int monitor-enter monitor-exit move move-exception move-object move-object/16 move-object/from16 move-result move-result-object move-result-wide move-wide move-wide/16 move-wide/from16 move/16 move/from16 mul-double mul-double/2addr mul-float mul-float/2addr mul-int mul-int/2addr mul-int/lit8 mul-int/lit16 mul-long mul-long/2addr neg-double neg-float neg-int neg-long new-array new-instance nop not-int not-long or-int or-int/2addr or-int/lit16 or-int/lit8 or-long or-long/2addr rem-double rem-double/2addr rem-float rem-float/2addr rem-int rem-int/2addr rem-int/lit16 rem-int/lit8 rem-long rem-long/2addr return return-object return-void return-wide rsub-int rsub-int/lit8 sget sget-boolean sget-byte sget-char sget-object sget-short sget-wide shl-int shl-int/2addr shl-int/lit8 shl-long shl-long/2addr shr-int shr-int/2addr shr-int/lit8 shr-long shr-long/2addr sparse-switch sput sput-boolean sput-byte sput-char sput-object sput-short sput-wide sub-double sub-double/2addr sub-float sub-float/2addr sub-int sub-int/2addr sub-int/lit16 sub-int/lit8 sub-long sub-long/2addr throw throw-verification-error ushr-int ushr-int/2addr ushr-int/lit8 ushr-long ushr-long/2addr xor-int xor-int/2addr xor-int/lit16 xor-int/lit8 xor-long xor-long/2addr</string> </dict> <dict> <key>Word2</key> <string>v0 v1 v2 v3 v4 v5 v6 v7 v8 v9 v10 v11 v12 v13 v14 v15 v16 v17 v18 v19 v20 v21 v22 v23 v24 v25 v26 v27 v28 v29 v30 v31 v32 v33 v34 v35 v36 v37 v38 v39 v40 v41 v42 v43 v44 v45 v46 v47 v48 v49 v50 p0 p1 p2 p3 p4 p5 p6 p7 p8 p9 p10 p11 p12 p13 p14 p15 p16 p17 p18 p19 p20 p21 p22 p23 p24 p25 p26 p27 p28 p29 p30</string> </dict> <dict> <key>Word3</key> <string>array-data .catch .catchall .class .end .end\ local .enum .epilogue .field .implements .line .local .locals .parameter .prologue .registers .restart .restart\ local .source .subannotation .super</string> </dict> <dict> <key>Word4</key> <string>abstract bridge constructor declared-synchronized enum final interface native private protected public static strictfp synchronized synthetic system transient varargs volatile</string> </dict> <dict> <key>Word4</key> <string>(&quot;0)&quot;0</string> </dict> <dict> <key>Word5</key> <string>.method .annotation .sparse-switch .packed-switch</string> </dict> <dict> <key>word6</key> <string>.end\ method .end\ annotation .end\ sparse-switch .end\ packed-switch</string> </dict> <dict> <key>word7</key> <string>&quot; ( ) , ; { } &gt;</string> </dict> <key>uuid</key> <string>27798CC6-6B1D-11D9-B8FA-000D93589AF6</string> </dict> </plist>

    Read the article

  • Fast sign in C++ float...are there any platform dependencies in this code?

    - by Patrick Niedzielski
    Searching online, I have found the following routine for calculating the sign of a float in IEEE format. This could easily be extended to a double, too. // returns 1.0f for positive floats, -1.0f for negative floats, 0.0f for zero inline float fast_sign(float f) { if (((int&)f & 0x7FFFFFFF)==0) return 0.f; // test exponent & mantissa bits: is input zero? else { float r = 1.0f; (int&)r |= ((int&)f & 0x80000000); // mask sign bit in f, set it in r if necessary return r; } } (Source: ``Fast sign for 32 bit floats'', Peter Schoffhauzer) I am weary to use this routine, though, because of the bit binary operations. I need my code to work on machines with different byte orders, but I am not sure how much of this the IEEE standard specifies, as I couldn't find the most recent version, published this year. Can someone tell me if this will work, regardless of the byte order of the machine? Thanks, Patrick

    Read the article

  • How do you convert an unsigned int[16] of hexidecimal to an unsigned char array without losing any information?

    - by user1068636
    I have a unsigned int[16] array that when printed out looks like this: 4418703544ED3F688AC208F53343AA59 The code used to print it out is this: for (i = 0; i < 16; i++) printf("%X", CipherBlock[i] / 16), printf("%X",CipherBlock[i] % 16); printf("\n"); I need to pass this unsigned int array "CipherBlock" into a decrypt() method that only takes unsigned char *. How do correctly memcpy everything from the "CipherBlock" array into an unsigned char array without losing information? My understanding is an unsigned int is 4 bytes and unsigned char 1 byte. Since "CipherBlock" is 16 unsigned integers, the total size in bytes = 16 * 4 = 64 bytes. Does this mean my unsigned char[] array needs to be 64 in length? If so, would the following work? unsigned char arr[64] = { '\0' }; memcpy(arr,CipherBlock,64); This does not seem to work. For some reason it only copies the the first byte of "CipherBlock" into "arr". The rest of "arr" is '\0' thereafter.

    Read the article

  • How to set up a functional macro with parameters in C++?

    - by user1728737
    is there a way that I can make this work? Or do I need to use separate files? #include <iostream> // Necessary using namespace std; long double primary, secondary, tertiary; #define long double mMaxOf2(long double min, long double max) { return ((max > min) ? (max) : (min)); } #define long double mMaxOf3(long double Min, long double Max, long double Mid) { long double Mid = (long double mMaxOf2(long double Min, long double Mid)); long double Max = (long double mMaxOf2(long double Mid, long double Max)); return (Max); } int main() { cout << "Please enter three numbers: "; cin << primary << secondary << tertiary; cout << "The maximum of " << primary << " " << secondary << " " << tertiary; cout << " using mMaxOf3 is " << long double mMaxOf3(primary, secondary, tertiary); return 0; } This is the error that I am getting. |20|error: expected unqualified-id before '{' token|

    Read the article

  • Compare sign of two doubles

    - by bobobobo
    What's the fastest way to compare sign on a double? I know that a double has a "sign bit" but I'm not sure if the way I'm "looking for it" in its binary rep is a good idea or not. Barring "portability" issues, can someone tell me what's going on with this code in MSVC++? #include <stdio.h> int main() { double z = 5.0 ; __int64 bitSign ; __int64 *ptr ; ptr = (__int64*)&z ; for( __int64 sh = 0 ; sh < 65 ; sh++ ) { bitSign = 1L << sh ; // Weird. it doesn't do 1. printf( "Bit# %d (%llx): %lld\n", sh, bitSign, ( (*ptr) & bitSign) ) ; } } First, why is starting at bit 32, even though I only shifted by one bit? Second, is it ok for me to check the 64th bit of a double to check its sign on MSVC++? Or is there a more preferred way?

    Read the article

  • Precision error on matrix multiplication

    - by Wam
    Hello all, Coding a matrix multiplication in my program, I get precision errors (inaccurate results for large matrices). Here's my code. The current object has data stored in a flattened array, row after row. Other matrix B has data stored in a flattened array, column after column (so I can use pointer arithmetic). protected double[,] multiply (IMatrix B) { int columns = B.columns; int rows = Rows; int size = Columns; double[,] result = new double[rows,columns]; for (int row = 0; row < rows; row++) { for (int col = 0; col < columns; col++) { unsafe { fixed (float* ptrThis = data) fixed (float* ptrB = B.Data) { float* mePtr = ptrThis + row*rows; float* bPtr = ptrB + col*columns; double value = 0.0; for (int i = 0; i < size; i++) { value += *(mePtr++) * *(bPtr++); } result[row, col] = value; } } } } } Actually, the code is a bit more complicated : I do the multiply thing for several chunks (so instead of having i from 0 to size, I go from localStart to localStop), then sum up the resulting matrices. My problem : for a big matrix I get precision error : NUnit.Framework.AssertionException: Error at (0,1) expected: <6.4209571409444209E+18> but was: <6.4207619776304906E+18> Any idea ?

    Read the article

  • c++ floating point precision loss: 3015/0.00025298219406977296

    - by SigTerm
    The problem. Microsoft Visual C++ 2005 compiler, 32bit windows xp sp3, amd 64 x2 cpu. Code: double a = 3015.0; double b = 0.00025298219406977296; //*((unsigned __int64*)(&a)) == 0x40a78e0000000000 //*((unsigned __int64*)(&b)) == 0x3f30945640000000 double f = a/b;//3015/0.00025298219406977296; the result of calculation (i.e. "f") is 11917835.000000000 (*((unsigned __int64*)(&f)) == 0x4166bb4160000000) although it should be 11917834.814763514 (i.e. *((unsigned __int64*)(&f)) == 0x4166bb415a128aef). I.e. fractional part is lost. Unfortunately, I need fractional part to be correct. Questions: 1) Why does this happen? 2) How can I fix the problem? Additional info: 0) The result is taken directly from "watch" window (it wasn't printed, and I didn't forget to set printing precision). I also provided hex dump of floating point variable, so I'm absolutely sure about calculation result. 1) The disassembly of f = a/b is: fld qword ptr [a] fdiv qword ptr [b] fstp qword ptr [f] 2) f = 3015/0.00025298219406977296; yields correct result (f == 11917834.814763514 , *((unsigned __int64*)(&f)) == 0x4166bb415a128aef ), but it looks like in this case result is simply calculated during compile-time: fld qword ptr [__real@4166bb415a128aef (828EA0h)] fstp qword ptr [f] So, how can I fix this problem? P.S. I've found a temporary workaround (i need only fractional part of division, so I simply use f = fmod(a/b)/b at the moment), but I still would like to know how to fix this problem properly - double precision is supposed to be 16 decimal digits, so such calculation isn't supposed to cause problems.

    Read the article

  • IOException reading a large file from a UNC path into a byte array using .NET

    - by Matt
    I am using the following code to attempt to read a large file (280Mb) into a byte array from a UNC path public void ReadWholeArray(string fileName, byte[] data) { int offset = 0; int remaining = data.Length; log.Debug("ReadWholeArray"); FileStream stream = new FileStream(fileName, FileMode.Open, FileAccess.Read); while (remaining > 0) { int read = stream.Read(data, offset, remaining); if (read <= 0) throw new EndOfStreamException (String.Format("End of stream reached with {0} bytes left to read", remaining)); remaining -= read; offset += read; } } This is blowing up with the following error. System.IO.IOException: Insufficient system resources exist to complete the requested If I run this using a local path it works fine, in my test case the UNC path is actually pointing to the local box. Any thoughts what is going on here ?

    Read the article

  • converting between struct and byte array

    - by chonch
    his question is about converting between a struct and a byte array. Many solutions are based around GCHandle.Alloc() and Marshal.StructureToPtr(). The problem is these calls generate garbage. For example, under Windows CE 6 R3 about 400 bytes of garbarge is made with a small structure. If the code below could be made to work the solution could be considered cleaner. It appears the sizeof() happens too late in the compile to work. public struct Data { public double a; public int b; public double c; } [StructLayout(LayoutKind.Explicit)] public unsafe struct DataWrapper { private static readonly int val = sizeof(Data); [FieldOffset(0)] public fixed byte Arr[val]; // "fixed" is to embed array instead of ref [FieldOffset(0)] public Data; // based on a C++ union }

    Read the article

  • reading a BYTE as a DWORD in Masm

    - by Help I'm in college
    Hi, once again I'm doing MASM programming. I'm trying to write a procedure using the Irvine32 library where the user enters a string which is put into an array of BYTEs with ReadString. Then it loops over that arrray and determines if each character is a number. However, when I try cmp [buffer + ecx], 30h MASM complains about comparing two things that are not the same size. Is there anyway I could read the ASCII code in each BYTE in the array as a DWORD (or otherwise extract the ASCII value in each BYTE)?

    Read the article

  • C# double-quoted path name being escaped when read from file

    - by KrisTrip
    I am trying to read in a text input file that contains a list of filenames (one per line). However, I am running into an issue if the user double-quotes the path (because it has a space in it). For example, a normal input file might have: C:\test\test.tiff C:\test\anothertest.tiff C:\test\lasttest.tiff These get read in fine by my code ("C:\\test\\test.tiff" etc) However, if I have the following input file: "C:\test with spaces\test.tiff" "C:\test with spaces\anothertest.tiff" "C:\test with spaces\lasttest.tiff" These get read in double-quotes and all ("\"C:\\test with spaces\\test.tiff\"" etc). This becomes a problem when I try to open the files (I understandably get invalid character exceptions). My question is, how do I fix this? I want to allow users to input quoted strings and handle them correctly. My first impression was to just write a little method that strips off beginning or ending quotes, but I thought there might be a better way.

    Read the article

  • byte[] operations in Java

    - by kape123
    Let's say I have array of bytes: byte[] arr = new byte[] { 0, 1, 2, 3, 4 }; Does platform has functions that I can use to play with this array - for example, how to invert it (get 4,3,2,1,0)? Or, how to invert part of it (2,1,0,3,4)? Get part of array (0,1,2,3)? I know I can manually write functions but I am curious if I'm missing useful util functions in platform that I should know about (and couldn't find any useful guide using google). Thanks!

    Read the article

  • Last byte missing when casting from varbinary to varchar

    - by xaxie
    I got the last byte losing when converting varbinary to varchar in some case. For example: DECLARE @binary varbinary(8000), @char varchar(8000) set @binary = 0x000082 set @char = CAST(@binary as varchar(8000)) select BinaryLength=DATALENGTH(@binary), CharLength=DATALENGTH(@char) The result is BinaryLength CharLength 3 2 The affected byte value is from 0x81 - 0xFE. The stranger thing is that if I use varchar(MAX) instead varchar(8000) when casting, there is no any problem. Could someone tell me the root cause of the issue? PS: I run the sql in MS SQL server 2008. Thanks!

    Read the article

  • Double of Total Problem

    - by Gopal
    Table1 ID | WorkTime ----------------- 001 | 10:50:00 001 | 00:00:00 002 | .... WorkTime Datatype is *varchar(. SELECT ID, CONVERT(varchar(10), TotalSeconds1 / 3600) + ':' + RIGHT('00' + CONVERT(varchar(2), (TotalSeconds1 - TotalSeconds1 / 3600 * 3600) / 60), 2) + ':' + RIGHT('00' + CONVERT(varchar(2), TotalSeconds1 - (TotalSeconds1 / 3600 * 3600 + (TotalSeconds1 - TotalSeconds1 / 3600 * 3600) / 60 * 60)), 2) AS TotalWork From ( SELECT ID, SUM(DATEDIFF(second, CONVERT(datetime, '1/1/1900'), CONVERT(datetime, '1/1/1900 ' + WorkTime))) AS TotalSeconds1 FROM table1 group by ID) AS tab1 where id = '001' The above Query is showing "double the total of time" For Example From table1 i want to calculate the total WorkTime, when i run the above query it is showing ID WorkTime 001 21:40:00 002..., But it should show like this ID Worktime 001 10:50:00 ..., How to avoid the double total of worktime. How to modify my query. Need Query Help

    Read the article

  • Efficient way to calculate byte length of a character, depending on the encoding

    - by BalusC
    What's the most efficient way to calculate the byte length of a character, taking the character encoding into account? In UTF-8 for example the characters have a variable byte length, so each character needs to be determined individually. As far now I've come up with this: char c = getItSomehow(); String encoding = "UTF-8"; int length = new String(new char[] { c }).getBytes(encoding).length; But this is clumsy and inefficient in a loop since a new String needs to be created everytime. I can't find other and more efficient ways in the Java API. I imagine that this can be done with bitwise operations like bit shifting, but that's my weak point and I'm unsure how to take the encoding into account here :) If you question the need for this, check this topic.

    Read the article

  • Pointer to auto_ptr instead of a classical double pointer

    - by Pin
    Hello. I'm quite new to smart pointers and was trying to refactor some existing code to use auto_ptr. The question I have is about double pointers and their auto_ptr equivalent, if that makes sense. I have a function that accepts a double pointer as its parameter and the function allocates resources for it: void foo ( Image** img ) { ... *img = new Image(); ...} This function is then used like this: Image* img = NULL; foo ( &img ); ... delete img; I want to use auto_ptr to avoid having to call delete explicitly. Is the following correct? void foo ( auto_ptr<Image>* img ); and then auto_ptr<Image> img = NULL; foo ( &img ); Thanks.

    Read the article

  • Double pointer as Objective-C block parameter

    - by George WS
    Is it possible (and if so, safe) to create/use a block which takes a double pointer as an argument? For instance: - (void)methodWithBlock:(void (^)(NSError **error))block; Additional context, research, and questions: I'm using ARC. When I declare the method above and attempt to call it, XCode autocompletes my method invocation as follows: [self methodWithBlock:^(NSError *__autoreleasing *error) {}]; What does __autoreleasing mean here and why is it being added? I presume it has something to do with ARC. If this is possible and safe, can the pointer still be dereferenced in the block as it would be anywhere else? In general, what are the important differences between doing what I'm describing, and simply passing a double pointer as a method parameter (e.g. - (void)methodWithDoublePointer:(NSError **)error;)? What special considerations, if any, should be taken into account (again assuming this is possible at all)?

    Read the article

< Previous Page | 19 20 21 22 23 24 25 26 27 28 29 30  | Next Page >