FunctionsBlock of statements with a name which perform an
operation on one or more values and return a resultFunctions are
reusable pieces of programsCan run at anytime anywhere in program
(Calling a function)
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Types:User defined functions creating our own function in
PythonBuilt in functionsPython with pre-defined functions
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User defined FunctionSyntax:def
fun_name(arguments/parameters):..Ex:
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defFunctions are defined using the keyword deffollowed by an
identifier name for the function followed by a pair of parentheses
which may enclose some names of variables and the line ends with a
colon.Followed by a block of statements that are part of this
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ParametersA function can take parameters which are just values
you supply to the function so that the function can do something
utilising those values.Parameters variables except that the values
of these are definedSpecified within parantheses seperated by
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Arguments and parameters
the names given in the function definition are called parameters
whereas the values you supply in the function call are called
arguments
def subtract(x,y): Parametersprint x-y def seq(ATGCC): Argument
print dna
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Return statement The return statement returns with a value from
a functionreturn without an expression argument returns
NoneSyntax:return_stmt ::= "return" [expression_list]If an
expression list is present, it is evaluated, else None is
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Reverse a sequenceJagsel Biosolutions
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Functions can call functionsJagsel Biosolutions
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Use of for and if statementJagsel Biosolutions
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Built in FunctionsPython interpreter has a number of functions
built into it that are always available.Most Frequently used built
in functions in python are:len()raw_input()open()Etc.,Jagsel
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len() and range()len()
range()
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split()Jagsel Biosolutions
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join()Jagsel Biosolutions
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Count() & reverse()Jagsel Biosolutions
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raw_input()Easiest way to obtain user input from the
command-line.Jagsel Biosolutions
