Nested for loop help
조회 수: 3 (최근 30일)
이전 댓글 표시
I'm trying to make a nested for loop to find prime numbers between 1 and 1000000 but I'm pretty sure I'm doing it wrong/got it stuck in an infinite loop because it's taking very long.
clear all
close all
primes = [ ];
tic
j=1
for m = 1:1000000 % outer loop
if isprime(m) == 1 % inner loop
primes(j) = m
j = j + 1;
m = m + 1;
else
end
m = m + 1;
end
toc
댓글 수: 2
Stephen23
2020년 3월 11일
Original question: "Nested for loop help"
I'm trying to make a nested for loop to find prime numbers between 1 and 1000000 but I'm pretty sure I'm doing it wrong/got it stuck in an infinite loop because it's taking very long.
clear all
close all
primes = [ ];
tic
j=1
for m = 1:1000000 % outer loop
if isprime(m) == 1 % inner loop
primes(j) = m
j = j + 1;
m = m + 1;
else
end
m = m + 1;
end
toc
채택된 답변
Ameer Hamza
2020년 3월 9일
Your logic is correct. However, in MATLAB, you don't need to increment the loop variable yourself, for the loop will automatically increment it. Apart from that, there is no infinite loop, it just takes a long time to complete
clear all;
close all;
primes_num = []; % name is changed because primes is also name of MATLAB built-in function
tic
j=1;
for m = 1:1000000 % outer loop
if isprime(m) == 1 % inner loop
primes_num(j) = m;
j = j + 1;
end
end
toc
You can also get the same answer using MATLAB built-in function
primes_num = primes(1000000);
댓글 수: 0
추가 답변 (0개)
참고 항목
카테고리
Help Center 및 File Exchange에서 Loops and Conditional Statements에 대해 자세히 알아보기
Community Treasure Hunt
Find the treasures in MATLAB Central and discover how the community can help you!
Start Hunting!