atof

问题 I have a list of numbers which looks like this: 1.234D+1 or 1.234D-02 . I want to read the file using C. The function atof will merely ignore the D and translate only the mantissa. The function fscanf will not accept the format '%10.6e' because it expects an E instead of a D in the exponent. When I ran into this problem in Python, I gave up and merely used a string substitution before converting from string to float. But in C, I am sure there must be another way . So, how would you read a

问题 This question already has an answer here : Android mupdf java.lang.UnsatisfiedLinkError: dlopen failed: cannot locate symbol “atof” (1 answer) Closed 3 years ago . I am trying to implement the mupdf library to render pdf documents in my app.My app crashes with the following error log:- java.lang.UnsatisfiedLinkError: dlopen failed: cannot locate symbol "atof" referenced by "libmupdf_java.so"... at java.lang.Runtime.loadLibrary(Runtime.java:364) at java.lang.System.loadLibrary(System.java:526)

问题 int main() { char str[10]="3.5"; printf("%lf",atof(str)); return 0; } This is a simple code I am testing at ideone.com. I am getting the output as -0.371627 回答1: You have not included stdlib.h. Add proper includes: #include <stdio.h> #include <stdlib.h> int main() { char str[10]="3.5"; printf("%lf",atof(str)); return 0; } Without including stdlib.h, atof() is declare implicitly and the compiler assumes it returns an int. 回答2: It could be undefined behavior. 来源： https://stackoverflow.com

问题 I am trying to convert a character array into double in c using atof and receiving ambiguous output. printf("%lf\n",atof("5")); prints 262144.000000 I am stunned. Can somebody explain me where am I going wrong? 回答1: Make sure you have included the headers for both atof and printf. Without prototypes the compiler will assume they return int values. When that happens the results are undefined, since that doesn't match atof's actual return type of double . #include <stdio.h> #include <stdlib.h>

问题 Hopefully this is a very simple question. Following is the C pgm (test.c) I have. #include <stdio.h> //#include <stdlib.h> int main (int argc, char *argv[]) { int intValue = atoi("1"); double doubleValue = atof("2"); fprintf(stdout,"The intValue is %d and the doubleValue is %g\n", intValue, doubleValue); return 0; } Note that I am using atoi() and atof() from stdlib.h, but I do not include that header file. I compile the pgm (gcc test.c) and get no compiler error! I run the pgm (./a.out) and

问题 I want to convert a section of a char array to a double. For example I have: char in_string[] = "4014.84954"; Say I want to convert the first 40 to a double with value 40.0 . My code so far: #include <stdio.h> #include <stdlib.h> int main(int arg) { char in_string[] = "4014.84954"; int i = 0; for(i = 0; i <= sizeof(in_string); i++) { printf("%c\n", in_string[i]); printf("%f\n", atof(&in_string[i])); } } In each loop atof it converts the char array from the starting pointer I supply all the

问题 I'm receiving data from my sensor via TCP and the output looks like this: <-0.040000 , -0.005000 , 0,025000 , 0,990000 , -0,000500 , 0.033000 > It's a 6 times double value. I need only first three. Forces in X,Y and Z direction to get their resultant force. I was told I'm reciving 'sensor streams string representation of double' and that I should use atof function which takes a string representing of a floating point number and returns a double. So, the problem is. I'm using following code to

问题 I'm experimenting with NIOS II soft core, trying to minimize the footprint of my embedded app. One of the biggest gains I get comes from using the small C library (p 206): The full newlib library functionality is often unnecessary for embedded systems, and undesirably large for systems needing a minimal RAM footprint. Altera provides a reduced-functionality reduced-size "Small C" version of newlib which allows smaller RAM footprints to be achieved. One of the features stripped down from small

问题 I am trying to convert a string to a double. The code is very simple. double first, second; first=atof(str_quan.c_str()); second=atof(extra[i+1].c_str()); cout<<first<<" "<<second<<endl; quantity=first/second; when trying to convert extra, the compiler throws this gem of wisdom at me: error: request for member c_str in extra.std::basic_string<_CharT, _Traits, _Alloc>::operator[] [with _CharT = char, _Traits = std::char_traits, _Alloc = std::allocator](((unsigned int)(i + 1))), which is of non

问题 I cannot get the atof() function to work. I only want the user to input values (in the form of decimal numbers) until they enter '|' and it to then break out the loop. I want the values to initially be read in as strings and then converted to doubles because I found in the past when I used this method of input, if you input the number '124' it breaks out of the loop because '124' is the code for the '|' char. I looked around and found out about the atof() function which apparently converts