double

问题 For the following code, #include <stdio.h> #include <limits.h> #include <float.h> int main(void) { printf("double max = %??\n", DBL_MAX); printf("double min = %??\n", DBL_MIN); printf("double epsilon = %??\n", DBL_EPSILON); printf("float epsilon = %??\n", FLT_EPSILON); printf("float max = %??\n", FLT_MAX); printf("float min = %??\n\n", FLT_MIN); return 0; } what specifiers would I have to use in place of the ??'s in order for printf to display the various quantities as appropriately-sized

问题 How do you read in a double from a file in C++? For ints I know you can use the getline() and then atoi, but I am not finding an array to double function. What is available for reading in doubles, or converting a char array to a double? 回答1: You can use stream extraction: std::ifstream ifs(...); double d; ifs >> d; This work provided that other then whitespace, the next data in the stream should be a double in textual representation. After the extraction, you can check the state of the stream

问题 I am trying to replace all \n\n on my server with the <BR> tag so that a single \n does not turn into <BR> . Example: Hello,\n\nThis is an\nexample.\n\nThanks! goes to: Hello,<BR>This is an\nexample,<BR>Thanks! (notice the single \n was not replaced) When I do the following in PHP, it does not replace the two lines with a break: $str = str_replace("\n\n", "<br />", $str); 回答1: Your \n are actually \r\n (which means the input came from a Windows operating system), I suggest you normalize you

问题 I've faced a weird case with a double variable after adding some values to it. The problem occurs when adding (0.2) to a double variable more than one time -I think it only happens with (0.2)- for example: consider this code: Dim i As Double = 2 i = i + 0.2 MsgBox(i) '2.2 MsgBox(i > 2.2) 'False >> No problem But if I add (0.2) more than one time: Dim i As Double = 2 i = i + 0.2 i = i + 0.2 MsgBox(i) '2.4 Msgbox(i > 2.4) 'True >> !!!! Also Dim i As Double = 2 For x As Integer = 1 to 5 i = i +

问题 I would like to pass the double value received from web page to sqlServer database. the value are wrapped in a value object. public class testVO{ Double value; public Double getValue() { return value; } public void setValue(Double value) { this.value = value; } } However, the problem I've met is when the value is smaller than 0.0001, it will transfer into 1.0E-4 or other scientific-notation, which causes the database error. The way I found is to use BigDecimal.valueOf(testVO.getValue()) to

问题 I'm converting a C++ system from solaris (SUN box and solaris compiler) to linux (intel box and gcc compiler). I'm running into several problems when dealing with large "long double" values. (We use "long double" due to some very very large integers... not for any decimal precision). It manifests itself in several weird ways but I've simplified it to the following program. It's trying to increment a number but doesn't. I don't get any compile or runtime errors... it just doesn't increment the

问题 I am managing some big (128~256bits) integers with gmp. It has come a point were I would like to multiply them for a double close to 1 (0.1 < double < 10), the result being still an approximated integer. A good example of the operation I need to do is the following: int i = 1000000000000000000 * 1.23456789 I searched in the gmp documentation but I didn't find a function for this, so I ended up writing this code which seems to work well: mpz_mult_d(mpz_class & r, const mpz_class & i, double d,

问题 Closed. This question is off-topic. It is not currently accepting answers. Want to improve this question? Update the question so it's on-topic for Stack Overflow. Closed 3 years ago . I am writing an Angular 2 application, And i can't understand why Angular can not properly work with <svg>. When i try to make SVG elements active with angular, i see errors in console. <rect x={{rect.x}} y={{rect.y}} width={{rect.width}} height={{rect.height}} fill={{rect.fill}} stroke={{rect.stroke}} /> <path

问题 I am currently trying to use UDP to send constant values from MATLAB to Simulink and then use Simulink to graph these values. Here is an image of the MATLAB code, Simulink block diagram and the graph that I am working with (note that the graph starts at a constant value of 0): http://i.imgur.com/krkulyQ.png In the MATLAB code I am using the fwrite function to send data to the Packet Input block which then outputs to the Scope block to graph the data. Specifically I would like to graph

问题 I am trying to establish some concise overview of what options for precise caluclations we have in JAVA+SQL. So far I have found following options: use doubles accepting their drawbacks, no go. use BigDecimals using them in complicated formulas is problematic for me use String.format/Decimal.format to round doubles do i need to round each variable in formula or just result to get BigDecimal precision? how can this be tweaked? use computed fields option in SQL. drawback is that I'd need