Hi. I have the following Problem. I want to show my Sensor Value from 0.0-100.0mm. But the Display shows just 0.-100. (for example not 22.9, just 22) On the Serial.print its correct. I guess its because of toCharArray... What could i do instead? Hope you can help 
Here is my program:
float analogPin = A6;
char printout[4];
byte led = 5;//byte: 8 bit (0-255)
#include <TFT.h>
#include <SPI.h>
#define CS 9 //TX
#define DC 0 //RX
#define RESET 1
TFT screen = TFT(CS, DC, RESET);
void setup() {
 // put your setup code here, to run once:
 Serial.begin(9600);
 screen.begin();
 screen.background(0, 0, 0); //Schwarzer Hintergrund
 screen.setTextSize(2);
 screen.stroke(255, 255, 255); //Weiß
 screen.text("mm", 0, 30);
 screen.setTextSize(3);
 screen.stroke(255, 0, 0); //Rot
 screen.line(0, 45, screen.width(), 45); //Rote Linie
}
void loop() {
 // put your main code here, to run repeatedly:
 analogPin = (100.0 / 1023 * analogRead(A6)); //Teilung des Analogwertes auf 0-100
 boolean overwrite;
 Serial.println(analogPin);
 Serial.println(overwrite);
 String analogPin = String(100.0 / 1023 * analogRead(A6));
 analogPin.toCharArray(printout, 4);
 screen.stroke(255, 255, 255); //Weiß
 screen.text(printout, 0, 5); //Analoger Wert an Display; Position x0y0
 if (analogRead(A6) >= 0 && (analogRead(A6) <= 11))
 {
  overwrite = true;
 }
 else if (analogRead(A6) >= 20 && (analogRead(A6) <= 31))
 {
  overwrite = true;
 }
 else if (analogRead(A6) >= 40 && (analogRead(A6) <= 51))
 {
  overwrite = true;
 }
 else if (analogRead(A6) >= 60 && (analogRead(A6) <= 71))
 {
  overwrite = true;
 }
 else if (analogRead(A6) >= 80 && (analogRead(A6) <= 91))
 {
  overwrite = true;
 }
 else if (analogRead(A6) >= 100 && (analogRead(A6) <= 111))
 {
  overwrite = true;
 }
 else if (analogRead(A6) >= 120 && (analogRead(A6) <= 131))
 {
  overwrite = true;
 }
 else if (analogRead(A6) >= 140 && (analogRead(A6) <= 151))
 {
  overwrite = true;
 }
 else if (analogRead(A6) >= 160 && (analogRead(A6) <= 171))
 {
  overwrite = true;
 }
 else if (analogRead(A6) >= 180 && (analogRead(A6) <= 191))
 {
  overwrite = true;
 }
 else if (analogRead(A6) >= 200 && (analogRead(A6) <= 211))
 {
  overwrite = true;
 }
 else if (analogRead(A6) >= 220 && (analogRead(A6) <= 231))
 {
  overwrite = true;
 }
 else if (analogRead(A6) >= 240 && (analogRead(A6) <= 251))
 {
  overwrite = true;
 }
 else if (analogRead(A6) >= 260 && (analogRead(A6) <= 271))
 {
  overwrite = true;
 }
 else if (analogRead(A6) >= 280 && (analogRead(A6) <= 291))
 {
  overwrite = true;
 }
 else if (analogRead(A6) >= 300 && (analogRead(A6) <= 311))
 {
  overwrite = true;
 }
 else if (analogRead(A6) >= 320 && (analogRead(A6) <= 331))
 {
  overwrite = true;
 }
 else if (analogRead(A6) >= 340 && (analogRead(A6) <= 351))
 {
  overwrite = true;
 }
 else if (analogRead(A6) >= 360 && (analogRead(A6) <= 371))
 {
  overwrite = true;
 }
 else if (analogRead(A6) >= 380 && (analogRead(A6) <= 391))
 {
  overwrite = true;
 }
 else if (analogRead(A6) >= 400 && (analogRead(A6) <= 411))
 {
  overwrite = true;
 }
 else if (analogRead(A6) >= 420 && (analogRead(A6) <= 431))
 {
  overwrite = true;
 }
 else if (analogRead(A6) >= 440 && (analogRead(A6) <= 451))
 {
  overwrite = true;
 }
 else if (analogRead(A6) >= 460 && (analogRead(A6) <= 471))
 {
  overwrite = true;
 }
 else if (analogRead(A6) >= 480 && (analogRead(A6) <= 491))
 {
  overwrite = true;
 }
 else if (analogRead(A6) >= 500 && (analogRead(A6) <= 511))
 {
  overwrite = true;
 }
 else if (analogRead(A6) >= 520 && (analogRead(A6) <= 531))
 {
  overwrite = true;
 }
 else if (analogRead(A6) >= 540 && (analogRead(A6) <= 551))
 {
  overwrite = true;
 }
 else if (analogRead(A6) >= 560 && (analogRead(A6) <= 571))
 {
  overwrite = true;
 }
 else if (analogRead(A6) >= 580 && (analogRead(A6) <= 591))
 {
  overwrite = true;
 }
 else if (analogRead(A6) >= 600 && (analogRead(A6) <= 611))
 {
  overwrite = true;
 }
 else if (analogRead(A6) >= 620 && (analogRead(A6) <= 631))
 {
  overwrite = true;
 }
 else if (analogRead(A6) >= 640 && (analogRead(A6) <= 651))
 {
  overwrite = true;
 }
 else if (analogRead(A6) >= 660 && (analogRead(A6) <= 671))
 {
  overwrite = true;
 }
 else if (analogRead(A6) >= 680 && (analogRead(A6) <= 691))
 {
  overwrite = true;
 }
 else if (analogRead(A6) >= 700 && (analogRead(A6) <= 711))
 {
  overwrite = true;
 }
 else if (analogRead(A6) >= 720 && (analogRead(A6) <= 731))
 {
  overwrite = true;
 }
 else if (analogRead(A6) >= 740 && (analogRead(A6) <= 751))
 {
  overwrite = true;
 }
 else if (analogRead(A6) >= 760 && (analogRead(A6) <= 771))
 {
  overwrite = true;
 }
 else if (analogRead(A6) >= 780 && (analogRead(A6) <= 791))
 {
  overwrite = true;
 }
 else if (analogRead(A6) >= 800 && (analogRead(A6) <= 811))
 {
  overwrite = true;
 }
 else if (analogRead(A6) >= 820 && (analogRead(A6) <= 831))
 {
  overwrite = true;
 }
 else if (analogRead(A6) >= 840 && (analogRead(A6) <= 851))
 {
  overwrite = true;
 }
 else if (analogRead(A6) >= 860 && (analogRead(A6) <= 871))
 {
  overwrite = true;
 }
 else if (analogRead(A6) >= 880 && (analogRead(A6) <= 891))
 {
  overwrite = true ;
 }
 else if (analogRead(A6) >= 900 && (analogRead(A6) <= 911))
 {
  overwrite = true;
 }
 else if (analogRead(A6) >= 920 && (analogRead(A6) <= 931))
 {
  overwrite = true;
 }
 else if (analogRead(A6) >= 940 && (analogRead(A6) <= 951))
 {
  overwrite = true;
 }
 else if (analogRead(A6) >= 960 && (analogRead(A6) <= 971))
 {
  overwrite = true;
 }
 else if (analogRead(A6) >= 980 && (analogRead(A6) <= 991))
 {
  overwrite = true;
 }
 else if (analogRead(A6) >= 1000 && (analogRead(A6) <= 1011))
 {
  overwrite = true;
 }
 else if (analogRead(A6) >= 1020)
 {
  overwrite = true;
 }
 if (overwrite = true)
 { screen.stroke(0, 0, 0);
  screen.text(printout, 0, 5);
 }
 else
 { (screen.stroke(255, 255, 255));
  screen.text(printout, 0, 5);
 }
}