1. LOOPS For
EE 201
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2. Class Learning Objectives
Achieve Comprehension LOL of using Loops in programming.
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3. Session Agenda Contact before work 5 min. For statements 70 min.
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4. Contact before work
Burning Questions
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5. Loops
A loop is a structure for repeating a calculation a number of times. Each repetition of the loop is a pass(iteration). MATLAB uses two types of explicit loops:
a-for loop: when the number of passes (iterations) is known ahead of time.
b-while loop : when the looping process must terminate when a specified condition is satisfied, and thus the number of passes is not known in advance.
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6. For loops
When we wish to repeat a set of instructions for a set number of times we generally use a for loop.
The Syntax:
for loop variable=initial value: increment value: end value
statements
end
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7. Flow chart for loop variable=initial value: increment value: end value
statements
end
Loop variable=
Initial value
Loop variable<=end value
loop variable=loop variable+increment
value T
statements F
end
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8. A simple example of a for loop isT
Start
K <=35
X = K ^ 2
End
K = K + 10
K=5
% for loop
for k = 5:10:35
% compute
x = k^2
end
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9. A simple example of a for loop is 1st iteration
Start
K <=35
X = K ^ 2
End
K = K + 10
K=5
% for loop
for k = 5:10:35
% compute
x = k^2
end
K=5
K=15
K=5
K=5
K=15
X=25
X=25
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10. A simple example of a for loop is 2nd iteration
Start
K <=35
X = K ^ 2
End
K = K + 10
K=5
% for loop
for k = 5:10:35
% compute
x = k^2
end
K=25
K=15
K=15
K=25
X=225
X=225
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11. A simple example of a for loop is 3rd iteration
Start
K <=35
X = K ^ 2
End
K = K + 10
K=5
% for loop
for k = 5:10:35
% compute
x = k^2
end
K=35
K=25
K=25
K=35
X=625
X=625
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12. A simple example of a for loop is 4th iteration
Start
K <=35
X = K ^ 2
End
K = K + 10
K=5
% for loop
for k = 5:10:35
% compute
x = k^2
end
K=45
K=35
K=35
K=45
X=1225
X=1225
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13. A simple example of a for loop is 5th iteration
Start
K <=35
X = K ^ 2
End
K = K + 10
K=5
% for loop
for k = 5:10:35
% compute
x = k^2
end
K=45
K=45
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14. Trace the previous example program and fill in the table below, which shows how the program variables change over the time of the execution of the program.
Iteration# k x
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15. Iteration# k x 1 5 25 2 15
225 3
625 4 35
1225
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16. Example
Draw a flowchart and Write a MATLAB program that finds the sum of first 50 natural numbers.
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17. Flowchart OR
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18. C SPRING 2012