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11 years, 6 months ago.
Convert a float number to string?
include the mbed library with this snippet
#include "mbed.h"
#include <string>
using std::string;
string data;
float temperature = 20.43;
data.append("SHT15 |C:");
data = data + to_string(temperature); //error identifier "to_string" is undefined
data.append("|F:");
data = data + to_string(this->get_Temperature_F()); //error
I try convert data from sensor to data type STRING. But this method convert does not work.
The compiler report error: identifier "to_string" is undefined. Why???
Example that I used is here: http://www.cplusplus.com/reference/string/to_string/
Thank you for your advice.
3 Answers
11 years, 6 months ago.
See the little warning message at the top of the page you link, that is only available in C++11, which isn't used here.
While you have to be a bit more careful, but in general working with (s)printf and char arrays is alot lighter on memory than using strings.
11 years, 6 months ago.
Hi Mark,
maybe you should try the sprintf function. I compile the code using mbed it seems to work but I did not try it on a hardware platform. Your number converted as a string should be under the buffer variable.
Check out http://www.cplusplus.com/reference/cstdio/sprintf/
#include "mbed.h"
#include "stdio.h"
DigitalOut myled(LED1);
int main() {
char buffer[50];
float c = 3.5;
n=sprintf (buffer, "%f", c);
while(1) {
myled = 1;
wait(0.2);
myled = 0;
wait(0.2);
}
}