Explain this please?

4 vues (au cours des 30 derniers jours)
Anne Nguyen
Anne Nguyen le 14 Oct 2019
x = 2;
e = 2.713;
c = 5 + (x < 2 || (e < pi));
c = 6
How does the value of c=6 after the code is executed? 2 is not less than 2, while e is not less than pi, so that is throwing me off. Thank you!
  2 commentaires
Mil Shastri
Mil Shastri le 14 Oct 2019
e = 2.713
pi = 3.1416
thus, (e < pi) indeed is true
Walter Roberson
Walter Roberson le 14 Oct 2019
But e is less than pi. 2.713 < 3.14159265358979323 [etc]

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Steven Lord
Steven Lord le 14 Oct 2019
c = 5 + (x < 2 || (e < pi));
Let's look at each section of the code inside the outer parentheses in turn.
x < 2
Since x is equal to 2, x < 2 is false.
(e < pi)
Since e is less than pi, this returns true. [By the way, you can use exp(1) to return the value of the constant e.]
(false || true)
This results in true.
So what is 5 + true? For many intents and purposes in MATLAB, you can think of false like 0 and true like 1. Indexing is the main exception; you can't index into an array with 0 but you can with false. [Search the documentation for "logical indexing" for more information on this.] So 5 + true is essentially 5 + 1 which results in 6.

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