Warning: Use of undefined constant n月 - assumed 'n月' (this will throw an Error in a future version of PHP) in /home/ubuntu/app/wordpress/wp-content/themes/inove/archive.php on line 47
12月
Warning: Use of undefined constant d - assumed 'd' (this will throw an Error in a future version of PHP) in /home/ubuntu/app/wordpress/wp-content/themes/inove/archive.php on line 49
15
Warning: Use of undefined constant n月 - assumed 'n月' (this will throw an Error in a future version of PHP) in /home/ubuntu/app/wordpress/wp-content/themes/inove/archive.php on line 47
11月
Warning: Use of undefined constant d - assumed 'd' (this will throw an Error in a future version of PHP) in /home/ubuntu/app/wordpress/wp-content/themes/inove/archive.php on line 49
24
Warning: Use of undefined constant n月 - assumed 'n月' (this will throw an Error in a future version of PHP) in /home/ubuntu/app/wordpress/wp-content/themes/inove/archive.php on line 47
11月
Warning: Use of undefined constant d - assumed 'd' (this will throw an Error in a future version of PHP) in /home/ubuntu/app/wordpress/wp-content/themes/inove/archive.php on line 49
10
Warning: Use of undefined constant n月 - assumed 'n月' (this will throw an Error in a future version of PHP) in /home/ubuntu/app/wordpress/wp-content/themes/inove/archive.php on line 47
7月
Warning: Use of undefined constant d - assumed 'd' (this will throw an Error in a future version of PHP) in /home/ubuntu/app/wordpress/wp-content/themes/inove/archive.php on line 49
09
Warning: Use of undefined constant n月 - assumed 'n月' (this will throw an Error in a future version of PHP) in /home/ubuntu/app/wordpress/wp-content/themes/inove/archive.php on line 47
8月
Warning: Use of undefined constant d - assumed 'd' (this will throw an Error in a future version of PHP) in /home/ubuntu/app/wordpress/wp-content/themes/inove/archive.php on line 49
02
假设我们有一小段正弦信号sin(2 π f t),不要考虑任何数字化的东西,这个f就叫做模拟频率。假设f=100,那么我们高中知识知道这个正弦信号的周期是1/f,也就是0.01,也就是说0.01的时间t里面正弦信号变化的一周,我们就知道从0到1里面变化了100次,也就是f次,所以我们才把f叫做频率的。 阅读全文…