This website requires Javascript to function properly. Please go to the setting of your web browser and enable Javascript for this website.

Ad by

推荐 OXIO 加拿大高速网络，最低月费仅$40. 使用推荐码 RCR37MB 可获得一个月的免费服务

Ad by

推荐 OXIO 加拿大高速网络，最低月费仅$40. 使用推荐码 RCR37MB 可获得一个月的免费服务

I could do better if I knew what the issue is. Please read new source codes inside.

doors(道士)

N1 = 80;
beita = 0.3;

// s3[N1][N1]
for(i = 0; i < N1; i++)
for(j = i; j < N1; j++)
s3[i][j] = s3[j][i] = exp(-beita * (i * i + j * j));

NN = 40;

nb3 = 0;
nb4 = NN - 1;
for(i = 0; i < N1; i++)
{
if(i > NN)
nb3++;

if(nb4 < N1)
nb4++;

nb1 = 0;
nb2 = NN - 1;
for(j = 0; j < N1; j++)
{
if(j > NN)
nb1++;

if(nb2 < N1)
nb2++;

aa = 0;
for(i1 = nb3; i1 < nb4; i1++)
{
for (j1 = nb1; j1 < nb2; j1++)
{
j2 = i > i1 ? i - i1 : i1 - i;
j3 = j > j1 ? j - j1 : j1 - j;

bb = s3[j2][j3] * s1[i1][j1];
if(aa < bb)
aa = bb;
}
}

s2[i][j] = aa;
}
}

(#185541@0)
Last Updated: 2001-8-31
This post has been archived. It cannot be replied.

Report

Replies, comments and Discussions:

工作学习 / IT技术讨论 / 各位编程高手请进，谢谢。 -guest:; 2001-8-30 {309} (#184601@0)
请问用VC++编程时，如果用到new来进行内存的分配，是否特别影响执行速度。我程序中的数组原先是30*30的，不用内存分配即可执行。可现在改成80*80的，就必须要用到内存分配，否则出错。原先运行程序只需要40多秒，可现在居然要一个半小时，太夸张了吧。请问会有这么大的差距吗?另外，如何能够提高执行的速度，恢复到原来的水平?谢谢。

up and help please!! -guest:; 2001-8-30 (#184637@0)
did you try C language? If the problem still exsits, you should check your algorithm -guest:; 2001-8-30 (#185163@0)
什么类型的数组？多半是算法问题，有否递归处理在你的程序中？ -takeoff(again); 2001-8-30 (#185261@0)

read it in 论坛热点区 I dont have good answer for that question -scorpio(scorpio); 2001-8-30 (#185283@0)

你真的很帮忙了，衷心感谢你。check your mail. -guest:; 2001-8-30 (#185295@0)

你的高见，谢谢了。具体情况见内。我的一个朋友说已经没办法简化算法了。 -guest:; 2001-8-30 {950} (#185300@0)
首先s1,s2是80*80的数组。inputN1=80,beita=0.3,其余均为变量
需要计算的公式是：
s2[p][q]=max(max(w(p-i,q-j)*s1[i][j]))
p,q,i,j from 0 to 79
w(m,n)=exp(-beita*(m^2+n^2))
m,n from -79 to 79

程序如下，已经进行了简化。
真正的计算是从第20行开始，前面都是为了简化计算。
我想问题就出在这里，我试着把这段程序用s2[i][j]=s1[i][j]代替，速度巨快。
不知道有什么办法能够优化这段程序呢?请一定赐教。谢谢。

1 NN=40;
2 for (i=0;i<inputN1;i=i+1)
3 {
4 for (j=0;j<inputN1;j=j+1)
5 {
6 nb1=j-NN;
7 if (nb1<0)
8 nb1=0;
9 nb2=j+NN;
10 if (nb2>inputN1)
11 nb2=inputN1;
12
13 nb3=i-NN;
14 if (nb3<0)
15 nb3=0;
16 nb4=i+NN;
17 if (nb4>inputN1)
18 nb4=inputN1;
19
20 aa=0;
21 for (i1=nb3;i1<nb4;i1=i1+1)
22 {
23 for (j1=nb1;j1<nb2;j1=j1+1)
24 {
25 j2=abs(i-i1);
26 j3=abs(j-j1);
27 fai=exp(-beita*(j2*j2+j3*j3));
28 bb=fai*s1[i1][j1];
29 if(aa<bb) aa=bb;
30 }
31 }
32 s2[i][j]=aa;
33 }
34 }

I could do better if I knew what the issue is. Please read new source codes inside. -doors(道士); 2001-8-31 {840} (#185541@0)
N1 = 80;
beita = 0.3;

// s3[N1][N1]
for(i = 0; i < N1; i++)
for(j = i; j < N1; j++)
s3[i][j] = s3[j][i] = exp(-beita * (i * i + j * j));

NN = 40;

nb3 = 0;
nb4 = NN - 1;
for(i = 0; i < N1; i++)
{
if(i > NN)
nb3++;

if(nb4 < N1)
nb4++;

nb1 = 0;
nb2 = NN - 1;
for(j = 0; j < N1; j++)
{
if(j > NN)
nb1++;

if(nb2 < N1)
nb2++;

aa = 0;
for(i1 = nb3; i1 < nb4; i1++)
{
for (j1 = nb1; j1 < nb2; j1++)
{
j2 = i > i1 ? i - i1 : i1 - i;
j3 = j > j1 ? j - j1 : j1 - j;

bb = s3[j2][j3] * s1[i1][j1];
if(aa < bb)
aa = bb;
}
}

s2[i][j] = aa;
}
}

Thank you for your help.You are really so kind!!!!!!!!! -guest:; 2001-8-31 (#185975@0)

wow, try this way check if the link exist /dev/diskette, or /dev/diskette0, this should point to /device/.... If the link looks ok, rm the file in /device... and 'reboot -- -r'. If null link, the floppy drive is bad. -guest:bigbai; 2001-8-31 (#186173@0)

????? -guest:; 2001-8-31 (#186178@0)
sorry, bug?! I was supposed to reply the topic below -guest:bigbai; 2001-8-31 (#186181@0)

@Las Vegas

I could do better if I knew what the issue is. Please read new source codes inside.

Replies, comments and Discussions:

More Topics