tag:blogger.com,1999:blog-486244449122404425.post3216986391154398264..comments2024-03-08T11:56:03.801+08:00Comments on 数据科学中的R和Python: 笨办法学R编程(4)写长城的诗http://www.blogger.com/profile/00652199274036685555noreply@blogger.comBlogger10125tag:blogger.com,1999:blog-486244449122404425.post-9474593089271742212013-05-14T19:20:34.645+08:002013-05-14T19:20:34.645+08:00goodgood写长城的诗https://www.blogger.com/profile/00652199274036685555noreply@blogger.comtag:blogger.com,1999:blog-486244449122404425.post-77881688287143577872013-05-14T09:58:06.609+08:002013-05-14T09:58:06.609+08:00可能是我电脑昨天有问题了 今天再运行就很快 ~可能是我电脑昨天有问题了 今天再运行就很快 ~Anonymousnoreply@blogger.comtag:blogger.com,1999:blog-486244449122404425.post-14105994298705856092013-05-13T17:55:16.618+08:002013-05-13T17:55:16.618+08:00最后一个搜索回文数的程序 我运行了好久都没运行出来 请问一下博主该程序的运行时间大概是多久?最后一个搜索回文数的程序 我运行了好久都没运行出来 请问一下博主该程序的运行时间大概是多久?Anonymousnoreply@blogger.comtag:blogger.com,1999:blog-486244449122404425.post-66623046316912154182012-09-01T07:01:54.288+08:002012-09-01T07:01:54.288+08:00这样做也蛮好,但就是没法知道是哪两个数字相乘得到的最终结果。这样做也蛮好,但就是没法知道是哪两个数字相乘得到的最终结果。写长城的诗https://www.blogger.com/profile/00652199274036685555noreply@blogger.comtag:blogger.com,1999:blog-486244449122404425.post-32229511788332560082012-09-01T07:00:11.853+08:002012-09-01T07:00:11.853+08:00是的,来看一下前六项。是的,来看一下前六项。写长城的诗https://www.blogger.com/profile/00652199274036685555noreply@blogger.comtag:blogger.com,1999:blog-486244449122404425.post-71054593843967953492012-09-01T01:33:08.490+08:002012-09-01T01:33:08.490+08:00请指教:
data <- data[order(data$prod,decreasing=T)...请指教:<br />data <- data[order(data$prod,decreasing=T),]<br />head(data) // 这句是用来检测 order 的结果的吗?<br /><br /><br />value <- data$prodvivizhyyhttps://www.blogger.com/profile/16072127546737981150noreply@blogger.comtag:blogger.com,1999:blog-486244449122404425.post-63345999765829851702012-08-31T17:06:53.429+08:002012-08-31T17:06:53.429+08:00我写了个投机取巧的计算方法。把100-999的所有三位数作为两个向量x和y,然后把x和y每一项的乘积...我写了个投机取巧的计算方法。把100-999的所有三位数作为两个向量x和y,然后把x和y每一项的乘积作为一个矩阵,再把矩阵转化为一个向量,从大到小验证向量的所有值,找出其中最大的一个回文数。<br /><br />x = 100:999<br />y = t(100:999)<br />mat = x %*% y<br />vec = as.vector(sort(mat))<br />i = 810000<br />while (i > 0){<br /> product = as.character(vec[i])<br /> reverse = paste(rev(strsplit(product,'')[[1]]),collapse='')<br /> if (reverse == product) break<br /> i = i - 1<br />}<br />print(product)bigcloudhttps://www.blogger.com/profile/02739342793655957584noreply@blogger.comtag:blogger.com,1999:blog-486244449122404425.post-76996432591560371692012-08-25T15:32:33.860+08:002012-08-25T15:32:33.860+08:00这个法子是可以的,转成字符嘛。例子中的reverse函数是用求余数的方法将个位上的数字提取,然后转到...这个法子是可以的,转成字符嘛。例子中的reverse函数是用求余数的方法将个位上的数字提取,然后转到十位上去,十位上的数字用整除变成个位数,如此循环。写长城的诗https://www.blogger.com/profile/00652199274036685555noreply@blogger.comtag:blogger.com,1999:blog-486244449122404425.post-35194826397497052702012-08-25T11:38:33.121+08:002012-08-25T11:38:33.121+08:00看不明白reverse function是怎么work的。我是用了个笨法子,好在数不是很多:
a&l...看不明白reverse function是怎么work的。我是用了个笨法子,好在数不是很多:<br />a<-c()<br />for(n in 999:100){<br /> for(m in 999:100){<br /> aa=m*n<br /> aa=as.character(aa)<br /> aa=unlist(strsplit(aa,""))<br /> bb=paste(aa,collapse="")<br /> cc=paste(rev(aa),collapse="")<br /> if(bb==cc) a<-c(a, m*n)<br /> }<br />}<br />max(a)Anonymoushttps://www.blogger.com/profile/12215033197059250069noreply@blogger.comtag:blogger.com,1999:blog-486244449122404425.post-16390356733312627322012-08-22T14:59:52.634+08:002012-08-22T14:59:52.634+08:00终于等到第四节了终于等到第四节了Anonymoushttps://www.blogger.com/profile/04158324830143326074noreply@blogger.com