alduxvm
Member
Hi!!
Im reading serial data that comes from a imu (razor 9dof, with a atmega onboard) when i read it, i store it in a char array, and in arduino, i just simply use atof, and it will be a floating variable, but, there is no atof define in the maple ide, right??
thanks!!
cheers!!
snigelen
Member
There's no atof, but it can be done (some way I don't remember exactly how). But I wrote a quick and dirty (no fancy stuff) atof a couple of days ago. Here it is
float my_atof(char *s)
{
float f = 0.0, fd = 0.0, d = 0.0;
int fe = 0;
char negative = 0, dp = 0;
while (isspace(*s) && *s != 0)
s++;
if (*s == '-') {
s++;
negative = 1;
}
while (isdigit(*s) && *s != 0 ) {
f *= 10;
f += (*s - '0');
s++;
}
// Decimals
if (*s == '.') {
s++;
d = 1.0;
while (isdigit(*s) && *s != 0 ) {
fd *= 10;
d *= 10;
fd += (*s - '0');
s++;
}
fd /= d;
}
f += fd;
if (negative)
f = -f;
// Exponent
if (*s == 'e' || *s == 'E') {
s++;
if (*s == '+') {
s++;
negative = 0;
} else if (*s == '-') {
s++;
negative = 1;
}
while (isdigit(*s) && *s != 0 ) {
fe *= 10;
fe += (*s - '0');
s++;
}
#if 1
if (negative)
fe = -fe;
f *= pow(10,fe);
#else
// A better way for this?
for (; fe; fe--)
if (negative)
f /= 10;
else
f *= 10;
#endif
}
return f;
}Not very well tested, but it seems to work for me (reading a couple of multimeters over rs232).
(Changed all "*s != tick backslash zero tick" to "*s != 0")
snigelen
Member
Sorry, I forgot to add
#include <ctype.h>
(and to remove the unused variable dp)
And to reset negative to zero if there's an exponent. Here's an updated version that also handles a leading '+'.
#include <ctype.h>
float my_atof(char *s)
{
float f = 0.0, fd = 0.0, d = 0.0;
int fe = 0;
char negative = 0;
while (isspace(*s) && *s != 0)
s++;
if (*s == '+')
s++;
if (*s == '-') {
s++;
negative = 1;
}
while (isdigit(*s) && *s != 0) {
f *= 10;
f += (*s - '0');
s++;
}
// Decimals
if (*s == '.') {
s++;
d = 1.0;
while (isdigit(*s) && *s != 0) {
fd *= 10;
d *= 10;
fd += (*s - '0');
s++;
}
fd /= d;
}
f += fd;
if (negative)
f = -f;
// Exponent
if (*s == 'e' || *s == 'E') {
s++;
negative = 0;
if (*s == '+') {
s++;
} else if (*s == '-') {
s++;
negative = 1;
}
while (isdigit(*s) && *s != 0 ) {
fe *= 10;
fe += (*s - '0');
s++;
}
if (negative)
fe = -fe;
#if 1
f *= pow(10,fe);
#else
// A better way for this?
for (; fe; fe--)
if (negative)
f /= 10;
else
f *= 10;
#endif
}
return f;
}
perry
Administrator
We link against newlib (a small libc variant), so atof should be available. #include <stdlib.h> should be enough.
alduxvm
Member
I have already test it, is my ide bad?? hehehehe, i #include <stdlib.h> , use the function, and when i compile, i get this errors:
Going to build using 'armcompiler' (ARM)
Compiling core...
Compiling libraries: Servo
Compiling the sketch...
/Applications/MapleIDE.app/Contents/Resources/Java/hardware/tools/arm/bin/../lib/gcc/arm-none-eabi/4.4.1/../../../../arm-none-eabi/include/stdlib.h:72: error: expected unqualified-id before 'int'
/Applications/MapleIDE.app/Contents/Resources/Java/hardware/tools/arm/bin/../lib/gcc/arm-none-eabi/4.4.1/../../../../arm-none-eabi/include/stdlib.h:72: error: expected ')' before 'int'
/Applications/MapleIDE.app/Contents/Resources/Java/hardware/tools/arm/bin/../lib/gcc/arm-none-eabi/4.4.1/../../../../arm-none-eabi/include/stdlib.h:72: error: expected ')' before 'int'
/Applications/MapleIDE.app/Contents/Resources/Java/hardware/tools/arm/bin/../lib/gcc/arm-none-eabi/4.4.1/../../../../arm-none-eabi/include/stdlib.h:72: error: expected ')' before 'int'
What could it be???
mbolivar
LeafLabs
Ok, we looked into it, and it's a bug in wirish_math.h (where we mimic the Arduino behavior by providing abs as a macro, instead of using math.h's version, which is a function).
newlib's stdlib.h seems to rely on abs being a function; since it's not, you get the compile error you posted.
We'll fix this in the next release. For now, does the implementation from snigelen work for you?
Bugtracker reference: http://code.google.com/p/leaflabs/issues/detail?id=57
alduxvm
Member
Its working!!!!
i found the issue...
i had the libraries in these position:
#include <Servo.h>
#include "contexto.h"
#include <stdlib.h>
and when compiling, always get that error...
i change stdlib to the upper position, and it worked...
#include <stdlib.h>
#include <Servo.h>
#include "contexto.h"
thanks a lot for the help!!
maple rocks!!!!!
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