D ATA T YPE. NUMBERS A number is an immutable type – means that changing or updating its value...

19
DATA TYPE

Transcript of D ATA T YPE. NUMBERS A number is an immutable type – means that changing or updating its value...

Page 1: D ATA T YPE. NUMBERS A number is an immutable type – means that changing or updating its value result in a newly allocated object. There are several types.

DATA TYPE

Page 2: D ATA T YPE. NUMBERS A number is an immutable type – means that changing or updating its value result in a newly allocated object. There are several types.

NUMBERS

A number is an immutable type – means that changing or updating its value result in a newly allocated object.

There are several types of numeric types – Integer Long integer Boolean Double –precision floating point real numbers Decimal floating point numbers Complex numbers

Page 3: D ATA T YPE. NUMBERS A number is an immutable type – means that changing or updating its value result in a newly allocated object. There are several types.

INTEGERS

There are several types of integers Boolean type – 2 possible values, True and False Actually an integer and behave like integer values

0 and 1 if used in numeric context. Standard Integers

Python standard integers are the universal numeric type.

Most machines (32-bit) running Python will provide a range of -231 to 231 -1 ( -2,147,483,648 to 2,147,483,647)

Example of integer : 0101, 84, -234,Ox80 etc Integers are normally represented in base 10

decimal format. It can also be represented in base 8 (octal, “0”

prefix)or base 16 (hexadecimal, “0x”/”OX” prefixes)

Page 4: D ATA T YPE. NUMBERS A number is an immutable type – means that changing or updating its value result in a newly allocated object. There are several types.

LONG INTEGERS

Longs are a superset of integers It is useful when your application requires

integers that exceed the range of plain /standard integers.

Use of longs is denoted by the letter ‘L’, uppercase (L) or lowercase (l), appended to the integer’s numeric values.

Values can be expressed in decimal , octal , or hexadecimal.

Examples : 16384L,-Ox4E8L ,-5432101234L,2997924581l

Page 5: D ATA T YPE. NUMBERS A number is an immutable type – means that changing or updating its value result in a newly allocated object. There are several types.

DOUBLE PRECISION FLOATING POINT NUMBERS

Floating point values are denoted by a decimal point (.) in the appropriate place and an optional “e” suffix representing scientific notation.

Can use either lowercase (e) or uppercase (E).

Positive (+)/negative (-) signs between the “e” and the exponent indicate the sign of the exponent.

No sign indicate positive exponent. Examples : 0.0, -5.55557119, -1.609E-

19,3.67 etc

Page 6: D ATA T YPE. NUMBERS A number is an immutable type – means that changing or updating its value result in a newly allocated object. There are several types.

COMPLEX NUMBERS

Combining a real number with an imaginary number

Example: 64.375 +1j, 0.23-8.55j,9.80665-8.31441J

Page 7: D ATA T YPE. NUMBERS A number is an immutable type – means that changing or updating its value result in a newly allocated object. There are several types.

OPERATORS-NUMERIC TYPE (ARITHMETIC )

Division Classic division

Using integer operands, classic division truncates the fraction, returning an integer (floor division).

Using a pair of floating point operands, it returns the actual floating-point quotient (true division).

Example :>>> 1/2 #perform integer result (floor)0>>> 1.0/2.0 #returns actual quotient0.5

Page 8: D ATA T YPE. NUMBERS A number is an immutable type – means that changing or updating its value result in a newly allocated object. There are several types.

CONTINUE

True division the division always returns the actual quotient

regardless of the type of the operands For now, to take advantage of true division, need

to give the from_future_import division directive. Once that happens, the division operator (/)

performs only true division. >>> from_future_import division >>>>>>1/20.5>>>1.0/2.00.5

Page 9: D ATA T YPE. NUMBERS A number is an immutable type – means that changing or updating its value result in a newly allocated object. There are several types.

CONTINUE

Floor division (//)- always truncates the fraction and rounds it

to the next smallest whole number toward the left on the number line, regardless of the operands’ numeric types.

Examples:>>> 1 // 20>>>1.0 // 2.0 0.0>>>-1 // 2-1

Page 10: D ATA T YPE. NUMBERS A number is an immutable type – means that changing or updating its value result in a newly allocated object. There are several types.

MODULUS

Integer modulus is straightforward integer division remainder .

Exponentiation Has a peculiar/strange precedence rule in its

relationship with the unary operators. It binds more tightly than unary operators to

its left, less tightly than unary operators to its right.

example:>>> 3 ** 29

Page 11: D ATA T YPE. NUMBERS A number is an immutable type – means that changing or updating its value result in a newly allocated object. There are several types.

CONTINUE

>>> -3 ** 2 # perform 3 to the power of two before applies the unary negation

-9>>> (-3) ** 29

Page 12: D ATA T YPE. NUMBERS A number is an immutable type – means that changing or updating its value result in a newly allocated object. There are several types.

EXAMPLES OF NUMERIC OPERATORS

>>> -442 -77-519>>> 4**364>>> 4.2 ** 3.298.7183139527>>> 8/32>>> 8.0/3.02.66666666667>>> 8 % 32

Page 13: D ATA T YPE. NUMBERS A number is an immutable type – means that changing or updating its value result in a newly allocated object. There are several types.

CONTINUE

>>> (60. -32.) * (5./9.)15.5555555556>>> 14 * 0x0456>>> 0170/430>>> 45L * 22L990L

Page 14: D ATA T YPE. NUMBERS A number is an immutable type – means that changing or updating its value result in a newly allocated object. There are several types.

NUMERIC TYPE FUNCTIONS

Function operation

bool (obj) Returns the boolean value of obj.

int (obj,base =10) Returns integer representing of string or number obj.

long (obj, base =10)

Returns long representation of string or number obj.

float (obj) Returns floating point representation of string or number obj

complex (str) Returns complex number representation of str, or builds one given real

Page 15: D ATA T YPE. NUMBERS A number is an immutable type – means that changing or updating its value result in a newly allocated object. There are several types.

EXAMPLES

>>> int (4.2555)4>>> long (42)42L>>> float(4)4.0>>>complex(4)(4+0j)

Page 16: D ATA T YPE. NUMBERS A number is an immutable type – means that changing or updating its value result in a newly allocated object. There are several types.

OPERATIONAL Python has five operational built-in function

for numeric types: abs() – returns the absolute value of the given

argument. If the argument is a complex number, then math.sqrt(num.real2 +num.imag2) is returned.

coerce ( ) – returns a tuple containing the converted pair of numbers.

divmod ( ) –combines division and modulus operations into a single function. The values returned are the same as those given for

the classic division and modulus operator for integer type.

As for float, the quotient returned math.floor(num1/num2).

As for complex numbers, the quotient is math.floor((num1/num2).real)

Page 17: D ATA T YPE. NUMBERS A number is an immutable type – means that changing or updating its value result in a newly allocated object. There are several types.

CONTINUE

pow ( ) – pow () and ** perform exponentiation, one is operator (**), and the other is build-in function.

round ( ) – has a syntax of round(flt,ndig=0) rounds a floating point number to the nearest integral

number and returns that result still in a float. When the optional ndig is given, round () will round the

argument to the specific number of decimal places.

Page 18: D ATA T YPE. NUMBERS A number is an immutable type – means that changing or updating its value result in a newly allocated object. There are several types.

EXAMPLE

abs ()>>> abs(-1)1>>> abs (10.)10.0>>> abs (0.23-

0.78)0.55

• coerce ()>>> coerce(1,2)(1,2)>>>coerce (1,134L)(1L,134L)

Page 19: D ATA T YPE. NUMBERS A number is an immutable type – means that changing or updating its value result in a newly allocated object. There are several types.

CONTINUE WITH EXAMPLES

>>>divmod(10,3)(3,1)>>> divmod (3,10)(0,3)

>>> pow(2,5)32

>>> round (3)3.0>>> round(3.49999,1)3.5

>>> bool(1)True>>> bool(True)True>>> bool(‘1’)True