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Message: <blockquote data-quote="x-pert" data-source="post: 677252" data-attributes="member: 837">Please go through <a href="http://www.elakiri.com/forum/showthread.php?t=35788" target="_blank">Lesson 01</a><a href="http://www.elakiri.com/forum/showthread.php?t=35876" target="_blank">Lesson 02</a><a href="http://www.elakiri.com/forum/showthread.php?t=36705" target="_blank">Lesson 03</a><a href="http://www.elakiri.com/forum/showthread.php?t=36710" target="_blank">Lesson 04</a> and <a href="http://www.elakiri.com/forum/showthread.php?t=37535" target="_blank">Lesson 05</a> before reading this lesson. Actually this is a continuation of <a href="http://www.elakiri.com/forum/showthread.php?t=37535" target="_blank">Lesson 05</a>. Floating point numbersC language uses a Decimal point (Dashama thitha) to distinguish between integers and floating point numbers. Floating point numbers always contain a decimal point. Numbers such as 5.0, 34.56, 23.5, 122.25 can be considered as floating point numbers. KEEP IN MIND numbers such as 12, 3 and 666 are integers and 12.0, 3.0 and 666.0 are floating point numbers. (If you add a decimal point to the digit, it will become a float value.) A floating point zero should be written as 0.0And you can store exponential numbers in floating point type as well. You have to use e to denote an exponential number. 7.5e27  means  7.5 X 1027The general form of defining a floating point variable is almost the same as defining an inger, but except int key word, you have to use floatfloat variable_name;  /*comment*/Like integers, floating point numbers also have limitations. We will discuss it in another lesson. e.g. find the answer of the expression 1.0 / 3.0 Simply we can do it by#include <stdio.h>int main(){printf("The answer is %f\n", 1.0/3.0);return (0);}DID YOU NOTICE WE HAVE USED %f as the place holder this time....Earlier for Integers we used %d and for floating point numbers we have to use %fDivision operator is a special operator ( / ) Remember that there is a difference between integer division and float division. In integer division, the fraction part will be discarded. So you won’t get the fraction part in the result. 17/10 in integer division will give you the result as 1 .7 will get discarded. But on the other hand you will get the correct result as 1.7 if you divide float values 17.0 / 10.0If either of the Denominator (haraya) or numerator (lawaya) is a float value, you will get the result as a float. So 17.0/10 ,   17/10.0   or  17.0/10.0 will give you a correct floating point value. BUT NOT 17/10e.g. 1 + 2 = 3  (Integer)10/10 = 1 (Integer)10.0/10 = 1.0 (float)23/10 = 2 (Int) In here, since both the denominator and numerator are integers, the .3 will be discarded. 23.0/10.0 = 2.3 (float)C language allows automatic conversion of integer to floating point numbers:And it is possible to convert floating point numbers to integers. But the fraction part will be discarded. (Part after the dashama thitha will be discarded)#include <stdio.h>int any_integer;    /*integer type variable named integer*/float any_float;   /*floating point type variable named float*/int main{any_float = 2.0 / 4.0;          /*this will assign 0.5 to any_float*/integer = 2/5;                    /*this will assign 0 to integer variable*/any_float = (2/5) + (2/5);      /*this will assign 0 to any_float....... Why did this happen...?? the correct answer should be 0.8.... But why it is 0.....??? */   /* You have to figure out why this happens..... even though the any_float variable is a floating point number, we divide two integers (2/5) and not two floating point numbers like 2.0/5.0 So 2/5 is 0 when consider integer division and 0 + 0 is still 0. That’s why you got the answer as 0 in the above example code line */any_float = 6.0/4.0    /*assigns 1.5 to the any_float variable*/integer = any_float   /* now we are asking the program to assign the value of any_float to integer variable. any_float has the value 1.5 coz of the line above... (6.0/4.0). But integer cannot contain a fraction part. So integer variable will now assigned 1.... just 1... And it has to discard the .5   */return (0);}Just for an experiment.... If you like to print each and every result on the screen, just add a printf() line after each expression and see whether what I’m telling is true.. <img src="/styles/default/xenforo/smilies/default/happy.gif"  class="smilie" loading="lazy" alt=":)" title="Happy    :)" data-shortname=":)" /> <img src="/styles/default/xenforo/smilies/default/happy.gif"  class="smilie" loading="lazy" alt=":)" title="Happy    :)" data-shortname=":)" /> <img src="/styles/default/xenforo/smilies/default/happy.gif"  class="smilie" loading="lazy" alt=":)" title="Happy    :)" data-shortname=":)" />If you followed the lesson correctly, this is not a big deal... But still if you need any help just let me know.... <img src="/styles/default/xenforo/smilies/default/happy.gif"  class="smilie" loading="lazy" alt=":)" title="Happy    :)" data-shortname=":)" /> <img src="/styles/default/xenforo/smilies/default/happy.gif"  class="smilie" loading="lazy" alt=":)" title="Happy    :)" data-shortname=":)" />CharactersCharacter type variables are denoted by char. General form of defining a character type variable is char variable_name   /*comment*/Characters are enclosed in single quotes like ‘A’.   ‘A’ , ‘a’,  ‘!’ are character constants. Backslash character is called the escape character ( \ )\b                     :      Backspace (Moves the cursor to the left by one character)\t                    :    Tab (moves the cursor to the right by one tab stop and usually there are 8 tab spaces in a standard screen)\n                 :     new line (Moves the cursor to the beginning of next line)\f            :   From feed (moves the cursor to the top of a new page)\r          :    return (moves cursor to the beginning of the current line) \’                   :  Apostrophe character ( ‘  )\”               :  Double quote  ( “ )\\          :     Backslash ( \ )\nnn                   :    character number in octal (ASCII)Characters are enclosed in single quotes (‘a’) and strings are enclosed in double quotes (“string”)When using the printf function to print a character on the string. You have to use the %c place holder. Example (Taken from the source book)#include <stdio.h>char char1; /* first character */char char2; /* second character */char char3; /* third character */int main(){char1 = 'A';  /* we are assigning A to variable char1*/char2 = 'B';  /* assigns B to variable char2*/char3 = 'C';   /*assignes C to variable char3*/printf("%c%c%c reversed is %c%c%c\n",char1, char2, char3,char3, char2, char1);return (0);}First three %c place holders will get A B and C and the second set of three %c  place holders will get C B and A accordingly. Hope you can understand this coding. If you didn’t, please see the last lesson where I have used a diagram to show this. To explain it further...........<img src="http://img367.imageshack.us/img367/6560/pic3cqw0.jpg" alt="" class="fr-fic fr-dii fr-draggable " style="" />Next lesson will be on arrays and capturing inputs from the key board.Cheers...!!!</blockquote>

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