{[ promptMessage ]}

Bookmark it

{[ promptMessage ]}

l05_6up

# l05_6up - Pure and Eectful Functions CSci 1113 C/C for...

This preview shows pages 1–2. Sign up to view the full content.

: CSci 1113 C/C++ for Scientists and Engineers Section 010 - evening class Functions Prof. Eric Van Wyk and Ted Kaminski Spring 2010 c Van Wyk and Kaminski CSci 1113: C/C++ for Scientists and Engineers, evening class Spring 2010 Page 1 / 18 Pure and Effectful Functions : Sample functions Mathematics double x = cos(0.34) ; double p = pow(2.0,5.0); Random numbers srand(seed); Seeds the pseudo-random number generator. r = rand(); Returns the next pseudo-random number. Need to include <cstdlib> . c Van Wyk and Kaminski CSci 1113: C/C++ for Scientists and Engineers, evening class Spring 2010 Page 2 / 18 Pure and Effectful Functions : How can we modify Random.cpp to generate random integer numbers between a specified range? Say, between 1 and some value n ? How can we modify it to generate floating point random numbers in the range [0,1] ? http://www.cplusplus.com is a reasonable reference. See also http://www.cppreference.com/ . c Van Wyk and Kaminski CSci 1113: C/C++ for Scientists and Engineers, evening class Spring 2010 Page 3 / 18 Pure and Effectful Functions : Exercise 5.1 Modify your square root program to assign a value to guess randomly. What effect does this have on the behavior of your program? c Van Wyk and Kaminski CSci 1113: C/C++ for Scientists and Engineers, evening class Spring 2010 Page 3 / 18 Pure and Effectful Functions : Pure and impure functions Most functions are pure functions . A pure function always returns the same result when given the same input and have now effect on program variables. (Except when the result of the function call is assigned to a variable.) For example, cos and pow are pure functions. Both srand and rand are not pure, or impure .

This preview has intentionally blurred sections. Sign up to view the full version.

View Full Document
This is the end of the preview. Sign up to access the rest of the document.

{[ snackBarMessage ]}

### What students are saying

• As a current student on this bumpy collegiate pathway, I stumbled upon Course Hero, where I can find study resources for nearly all my courses, get online help from tutors 24/7, and even share my old projects, papers, and lecture notes with other students.

Kiran Temple University Fox School of Business ‘17, Course Hero Intern

• I cannot even describe how much Course Hero helped me this summer. It’s truly become something I can always rely on and help me. In the end, I was not only able to survive summer classes, but I was able to thrive thanks to Course Hero.

Dana University of Pennsylvania ‘17, Course Hero Intern

• The ability to access any university’s resources through Course Hero proved invaluable in my case. I was behind on Tulane coursework and actually used UCLA’s materials to help me move forward and get everything together on time.

Jill Tulane University ‘16, Course Hero Intern