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Topic: Double to String?? How?? (Read 1 time) previous topic - next topic

Hello I'm new in this and I wanna know how I do to convert a double variable to string??

What I want is this: I got a variable string and I want to add the information that is a double variable

----> something like :  The voltage is = 5.32 V.

My first variable is a string one and is this : frame = "The voltage is = ", and the second one is a double one and is ---> X = analogRead(xpin)

I want to do something like -------------> frame += X

SOMETHING LIKE THAT.......................Somebody can help me?

Aeturnalus

#1
May 19, 2011, 07:47 am Last Edit: May 19, 2011, 07:50 am by Aeturnalus Reason: 1
Depends on if you're using a cstring (char*) or a String object (string)

The easier way is to use the String object: ([url]http://www.arduino.cc/en/Reference/String[/ur])

Code: [Select]

 String frame = "The voltage is = " + String(analogRead(xpin), DEC) + " V\r\n";


With char*:

Code: [Select]

 char frame[30];
 sprintf(frame, "The voltage is = %.02f V.\r\n", analogRead(xpin));

johnwasser

Uh....  analogRead() returns an unsigned long integer, not a double (double-precision float).
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Aeturnalus

I thought the analogRead was an example... or not?

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