arduino compile error

Did you use the same program given in that link or did you make any modifications? I tried the same program from the link and it compiled properly for me.

Its always a good practice to paste your code in the forum rather than pointing it to a link. This way people can help you a bit more better

Here is the code as copied directly from the sketch editor:

#include<dht.h>      // Including library for dht
#include<LiquidCrystal.h>
LiquidCrystal lcd(7, 6, 5, 4, 3, 2);

#define dht_dpin 12 
dht DHT;

#define pwm 9

byte degree[8] = 
              {
                0b00011,
                0b00011,
                0b00000,
                0b00000,
                0b00000,
                0b00000,
                0b00000,
                0b00000
              };

void setup()
{
 lcd.begin(16, 2);
 lcd.createChar(1, degree);
 lcd.clear();
 lcd.print("   Fan Speed  ");
 lcd.setCursor(0,1);
 lcd.print("  Controlling ");
 delay(2000);
 analogWrite(pwm, 255);
 lcd.clear();
 lcd.print("Circuit Digest ");
 delay(2000);
}

void loop()
{
  DHT.read11(dht_dpin);
  int temp=DHT.temperature;
  lcd.setCursor(0,0);
  lcd.print("Temperature:");
  lcd.print(temp);   // Printing temperature on LCD
  lcd.write(1);
  lcd.print("C");
  lcd.setCursor(0,1);
  if(temp <26 )
    { 
      analogWrite(9,0);
      lcd.print("Fan OFF            ");
      delay(100);
    }
    
    else if(temp==26)
    {
      analogWrite(pwm, 51);
      lcd.print("Fan Speed: 20%   ");
      delay(100);
    }
    
     else if(temp==27)
    {
      analogWrite(pwm, 102);
      lcd.print("Fan Speed: 40%   ");
      delay(100);
    }void setup() {
  // put your setup code here, to run once:

}

Which results in the following error messages:

sketch_dec27a:6: error: 'dht' does not name a type

sketch_dec27a:6: error: 'dht' does not name a type

 dht DHT;

 ^

C:\Users\wfene\OneDrive\Documents\Arduino\sketch_dec27a\sketch_dec27a.ino: In function 'void loop()':

sketch_dec27a:39: error: expected unqualified-id before '.' token

   DHT.read11(dht_dpin);

      ^

sketch_dec27a:40: error: expected primary-expression before '.' token

   int temp=DHT.temperature;

               ^

exit status 1
'dht' does not name a type

* If I could just get past the 'dht DHT;  I'm sure the rest can be sorted out.  I wonder if the 'copy > paste' I do causes the error but the code looks just like the listing on the project page.  I have 5 of these DHT sensors and have ideas for all !  If I never get the code sorted for them they are useless !

Thanks in advance for your help.

After much surfing I concluded that the error was based on which 'dth lib ' one used !  One github repository actually bemoaned the fact that the syntax in the various dthlib s varied widely and because the sketch code [c++] is case sensitive beginners like me will chase errors because of this.

Bottom line I found one that had sample code syntax which I transposed to my project and got to compile !