Line 1 contains thewhilecommand, followed by a condition e. g.x>10.
This means as long as the condition,x>10, remains true the loop will
continually repeat.
Line 2 contains the body of loop which can be a command or series of
commands that will be executed on each iteration of the loop.
Line 3 contains theendcommand which must always be used at the end
of a loop to close it.
Listing 5.5 gives an example of a simplewhileloop which displays the value
of the variablex.
Listing 5.5: Simple example of awhileloop
1 >> x=1;
2 >> while x<10
3 x
4 x=x+1;
5 end
6 x =
7 1
8 x =
9 2
10 x =
11 3
12 x =
13 4
14 x =
15 5
16 x =
17 6
18 x =
19 7
20 x =
21 8
22 x =
23 9
Comments:
Line 1 assigns the value of 1 to the variablex. Notice this is outside of
thewhileloop. If you don’t do this you will get an error because you
are testing whetherx<10butxhas never been defined. Remember to define
variables you use in
loops before you start
the loops themselves.
In Line 2 the condition,x<10, is specified. In this case the loop will
continue to repeat as long asxis less than 10. As soon asxis equal to
10 execution of the loop is stopped.
