Pascal嵌套中的Forward如何使用
【require】英 [r?'kwa??(r)] 美 [r?'kwa??r] The director required that we should work all night.主任要求我们通宵工作。
We must not propagate one method and require all localities to adopt it.我们在宣传上不要只讲一种办法,要求各地都照着去做。
【require】用法require的基本意思一是“需要”,二是“要求”,可用于明确表示因事物的内在必要性所引起的迫切需要或当务之急,也可用于指法律和规章制度的强制要求,还可用于形势紧急的迫切性。
引申可作“规定”“想要”解。
require是及物动词,接名词、代词、动名词、动词不定式或that从句作宾语,也可接以动词不定式或that从句作直接宾语的双宾语。
require接含有被动意义的非谓语动词时,不定式表示被动结构,而动名词表示主动结构; require接that从句时从句中的谓语动词要用虚拟式。
require后面接人时,可接介词of或from,接of表示“对…本身的要求”,接from表示“从…要求”; 后面接物时,则要用介词for。
require的过去分词required可用作形容词,在句中作定语。
【declare】英 [d?'kle?(r)] 美 [d?'kler] I now declare this meeting open.我现在宣布会议开幕。
Britain declared war on Germany in 1914.英国在1914年向德国宣战。
【declare】用法declare的基本意思是明确地、清楚地、正式地“宣布,宣告”,多用于官方场合。
引申可指“宣称”“断言”“申报”等。
declare既可用作及物动词,又可用作不及物动词。
用作及物动词时,其后接名词、代词或that从句作宾语。
不接动名词,也不接动词不定式。
可用于被动语态。
declare后可接由to be/as加名词、形容词、副词或介词短语充当补足语的复合宾语。
to be/as有时可以省略。
declare接复合结构时可以用动词不定式或由wh-引起的疑问词从句作宾语,但它们都由it代替,而它们本身则移到补语后面,此时它的补语多为形容词。
declare作不及物动词时常跟介词against表示“声明反对”,接for表示“宣布支持”。
I declare在美式英语里可表示有点惊异或不高兴,相当于“Oh my God!”。
PHP怎么获取本地i pc蛋蛋啊 在线求助
争议概述 在本教程中,我们将端到端地来解析一个时间序列预测工程,从下载数据集、定义问题到训练出最终模型并进行预测。
该工程并不面面俱到,但展示了如何通过系统性地处理时间序列预测问题,来快速获得好的结果。
我们将通过如下步骤来解析该工程 :环境配置.问题描述 测试工具链 持续性.数据分析 ARIMA 模型 模型验证 该部分提供一个解决时间序列预测问题的模板,你可以套用自己的数据集。
1. 环境配置 本教程假设在已安装好了SciPy及其相关依赖库的环境下进行,包括:SciPy NumPy Matplotlib Pandas scikit-learn statsmodels 我使用的是Python2.7。
该脚本将帮助你确认你安装这些库的版本。
# scipy import scipy print('scipy: {}'.format(scipy.__version__))# numpy import numpy print('numpy: {}'.format(numpy.__version__))# matplotlib import matplotlib print('matplotlib: {}'.format(matplotlib.__version__))# pandas import pandas print('pandas: {}'.format(pandas.__version__))# scikit-learn import sklearn print('sklearn: {}'.format(sklearn.__version__))# statsmodels import statsmodels print('statsmodels: {}'.format(statsmodels.__version__)) 我编写该教程的所用的开发环境显示的结果如下:scipy: 0.18.1 numpy: 1.11.2 matplotlib: 1.5.3 pandas: 0.19.1 sklearn: 0.18.1 statsmodels: 0.6.1 2. 问题描述 我们研究的问题是预测美国波士顿每月持械抢劫案的数量。
该数据集提供了从1966年1月到1975年10月在波士顿每月发生的的武装抢劫案的数量, 或者说,是这十年间的数据。
这些值是一些记录的观察计数,总有118个观察值。
数据集来自于McCleary&Hay(1980)。
将数据集下载为CSV文件,并将其放在当前工作目录中,文件名为“robberies.csv”。
3.测试工具链 我们必须开发一套测试工具链来审查数据和评估候选模型。
这包含两个步骤:1.定义好验证数据集。
2.开发一套模型评估方法。
3.1 验证数据集 这个数据集不是当前时间段的数据集。
这意味着我们不能轻轻松松收集更新后的数据来验证该模型。
因此,我们假设现在是1974年10月,并将分析和模型选择的数据集里扣除最后一年的数据。
最后一年的数据将用于验证生成的最终模型。
下面的代码会加载该数据集为Pandas序列对象并将其切分成两部分,一个用于模型开发(dataset.csv)和另一个用于验证(validation.csv)。
from pandas import Series series = Series.from_csv('robberies.csv', header=0) split_point = len(series) - 12 dataset, validation = series[0:split_point], series[split_point:] print('Dataset %d, Validation %d' % (len(dataset), len(validation))) dataset.to_csv('dataset.csv') validation.to_csv('validation.csv') 运行该示例将会创建两个文件并打印出每个文件中的观察数。
1. Dataset 106, Validation 12 这些文件的具体内容是:dataset.csv:1966年1月至1974年10月的观察(106次观察) validation.csv:1974年11月至1975年10月的观察(12次观察) 验证数据集大小是原始数据集的10%。
请注意,由于保存的数据集中没有标题行,因此,稍后处理这些文件时,我们也不需要满足此要求。
3.2. 模型验证 模型评估将仅对上一节中准备的dataset.csv中的数据进行处理。
模型评估涉及两个要素:1. 评价指标。
2. 测试策略。
3.2.1评价指标 这些观察值是抢劫案的计数。
我们将使用均方根误差(RMSE)的方式来评价预测的好坏。
这将给予错误的预测更多的权重,并且将具有与原始数据相同的单位。
在RMSE进行计算和报告之前,必须反转对数据的所有转换,以使不同方法的效果可直接比较。
我们可以使用scikit-learn库的辅助函数mean_squared_error()来执行RMSE计算,该函数计算出了预期值列表(测试集)和预测列表之间的均方误差。
然后我们可以取这个值的平方根来作为一个RMSE分数。
例如: from sklearn.metrics import mean_squared_error from math import sqrt...test = ...predictions = ...mse = mean_squared_error(test, predictions) rmse = sqrt(mse) print('RMSE: %.3f' % rmse)3.2.2 测试策略 将使用步进验证的方式(walk-forward)来评估候选模型。
这是因为该问题定义需要滚动式预测的模型。
给定所有可用数据,这需要逐步进行预测。
步进验证的方式将按照如下几步执行:数据集的前50%将被用来训练模型。
剩余的50%的数据集将被迭代并测试模型。
对于测试数据集中的每个步骤:训练该模型 利用该模型预测一次,并经预测结果保存下来用于之后的验证 测试数据集的数据作为下一个迭代的训练集数据 对在测试数据集迭代期间进行的预测结果进行评估,并报告RMSE得分。
由于较小的数据规模,我们将允许在每次预测之前,在给定所有可用数据的情况下重新训练模型。
我们可以使用简单的NumPy和Python来编写测试工具的代码。
首先,我们可以将数据集直接分成训练和测试集。
我们总要将加载的数据转换为float32类型,以防止仍然有一些数据为String或Integer数据类型。
# prepare data X = series.values X = X.astype('float32') train_size = int(len(X) * 0.50) train, test = X[0:train_size], X[train_size:] 接下来,我们可以时间步长遍历测试数据集。
...
求高手给一份c程序,用rpr220黑白循迹模块进行小车黑白循迹,有急...
#include #define uchar unsigned char; //char单字节整型数据或字符型数据#define uint unsigned int; //int声明基本整型数据#define PON 0#define POFF 1#define ON 1#define OFF 0#define SPEED2 100#define SPEED1 50 uchar ito=0; uchar m=0; uchar time=0; uchar PWM1=0; uchar PWM2=0; sbit p=P2^0; //控制左轮 sbit q=P2^1; //控制右轮 sbit p_green=P2^2; sbit p_red=P2^3; sbit TCRD1=P2^4;//此处是传感器RPR220管脚位声明 sbit TCRD2=P2^5; sbit TCRD3=P2^6; sbit TCRD4=P2^7; int count1=0;//用于定时计数的两个全局变量位声明 int count2=0; int x[4]; uchar table1[]={ 0x28, 0x7E, 0xA2, 0x62, 0x74, 0x61, 0x21, 0x7A, 0x20, 0x60,0xff};//0,1,2,3,4,5,6,7,8,9,关显示,数码管码表,高电平有效 unsigned char code table2[]= {0xfe,0xfd,0xfb, //11111110,11111101,11111011 0xf7,0xef,0xdf,0xbf,0x7f,}; //11110111,11101111,11011111,10111111,01111111 unsigned char dp=0x7f; //Use AND to add the decimal point/clock point.unsigned char cp; int s=0; int sec=0; //定义路程,时间 char a; int idi=0; int j=0; bit rup3=0; int GAO=4000; int T=0;//处理时间中断3 int timeCount;//计时标志 int wheelCount;//测距标志//int white=0;//测交叉线 void delay(int x) { int a; int b; for(a=x;a>0;a--) for(b=125;b>0;b--); } void display()//显示时间和路程 { //显示时间 P0=table1[x[idi]]; P1=table2[idi]; idi++; if(idi==4) idi=0; delay(1); } void forward_turn1()//电机1前进 { if(PWM1) p=PON; else p=POFF; } void forward_turn2()//电机2前进 { if(PWM2) q=PON; else q=POFF; } void stop_turn1()//电机停止 { P=POFF; q=POFF; } void speed1(int ct,int sd)//电机1速度控制函数,其中参数 sd为生成 PWM 波 { if(ct>=sd) PWM1=0; else PWM1=1; } void speed2(int ct,int sd)//电机2速度控制函数,其中参数 sd为生成 PWM 波 { if(ct>=sd) PWM2=0; else PWM2=1; } void advance(int ct1,int sd1,int ct2,int sd2)//小车直线前进函数 { forward_turn1(); forward_turn2(); speed1(ct1,sd1); speed2(ct2,sd2); } //*************以下是方案1, 通过使两轮一快一慢来实现转向********* void left_turn1(int ct1,int sd1,int ct2,int sd2)//小车左转 { forward_turn1(); forward_turn2(); speed1(ct1,sd1); speed2(ct2,sd2); } void right_turn1(int ct1,int sd1,int ct2,int sd2)//小车右转 { forward_turn1(); forward_turn2(); speed1(ct1,sd1); speed2(ct2,sd2); } //*************以下是方案2, 通过使两轮一慢传,一停转来实现转向*** void left_turn2(int ct1,int sd1,int ct2,int sd2)//小车左转 { forward_turn1(); forward_turn2(); speed1(ct1,sd1); speed2(ct2,sd2); } void right_turn2(int ct1,int sd1,int ct2,int sd2)//小车右转 { forward_turn1(); stop_turn1(); speed1(ct1,sd1); speed2(ct2,sd2); } void main() { p=1; q=1; TMOD=0x11;//中断模式设置 TH0=(65536-1000)/256;//定时器1初始化 TL0=(65536-1000)%256; EA=1; ET0=1; TR0=1; TH1=(65536-1000)/256;//定时器2初始化 TL1=(65536-1000)%256; EA=1; ET1=1; TR1=1; while(1) { .............. } } void time0()interrupt 1 { TH0=(65536-5000)/256;//定时 5ms TL0=(65536-5000)%256; count1++; ito++; if(ito==200) { ito=0; s++; if(s==60) { s=0; m++; if(m==60) { m=0; } x[0]=m/10; x[1]=m%10; } x[2] =s/10; x[3] =s%10; } display(); if(count1==SPEED2)//周期是1s count1=0; count2++; if(count2==SPEED2)//周期是1s count2=0; }
外贸英语函电 译本的电子版,能不能也发我份啊,急用。
给你一份我们当时小组作业的资料吧。
。
里面有一些函电往来,你看看能不能参考一下喽。
。
1.买方询盘Dear Sir,We are glad to know your name and address on the Internet. We are interested in your product. We would like you to send us details of your various ranges, including sizes ,colors and prices, and also samples of the different qualities of material used.(about the production in other details)We take this opportunity to introduce ourselves to you as large dealers in production and believe there's a promising market in our area for moderately priced goods of the kind mentioned.If your prices and terms meet our requirements, we will be glad to start a business relationship with you.Looking forward to receiving an early reply.Yours faithfullyMili2.卖方回复:Dear madam,Enclosed is our new price list which will come into effect the end of this month. You will see that we have increased our prices on most models. We have, however, refrained from doing so on some models of which we hold large stocks. The explanation for our increased prices stems from the fact that we are now paying 10% more for our raw materials than we were paying last year, along with some of our subcontractors having raised their prices as much as 15%. As you know, we take great pride in our product an dare proud of the reputation for quality and dependability we have built over 15years. We will not compromise that reputation because of raising costs. We have, therefore, decided to raise the price of some of our products.We hope you will understand our position and look forward to your cooperation.With best regards,Mr liu3.卖方继续发盘Dear Madam,This is regarding our quotation dated 2 November, and our mail offer dated 8 November concerning the supply of Wood materials.We are prepared to keep our offer open until the end of this month.For your information, the market is firm and growing. There is very little likelihood of any significant change in the visible future. As this product is in great demand and the supply is limited, to secure your order, we would recommend that you accept this offer without delay.Yours sincerely,Mr liu4.买方还盘Dear Sir :Thank you for your mail. We are disappointed to hear that our price for your required product is too high for your acceptance. You mentioned that Japanese goods are being offered to you at a price approximately 8% lower than our quote.We accept your position, but we are of the opinion that the quality of the other makes does not measure up to that of our products. Although we are keen to do business with you, we regret that we cannot accept your counter offer.We do want to try and work with you, and meet your request, but the best we can do is to reduce our previous quotation by 3%.We hope that this will meet your approval.We look forward to hearing from you.With best regards,Mili5.买方还盘Dear Madam:Thank you for your order of 500 sets by your letter dated 17 July. We have considered your proposal to pay by a 30-day letter of credit. We do not usually accept time credit; however, in view of our long and mutually beneficial relationship, we are willing to make an exception this time. I must stress that this departure from our usual practice relates to this transaction only. This one-time accommodation does not set a precedent for future transactions. I am enclosing our sales contract No.834 covering the order. I would be grateful if you would follow the usual procedure. Yours sincerely,Mr liu6买方回复卖方:Dear Sir :Thank you for your letter dated 2 October requesting payment against documents for contracts No.482 and 483. We are pleased to say that we agree to your request. We wish, however, to make it clear that in our future transactions, involved for each transaction is less than US$375. Should the amount exceed that figure, payment by letter of credit will be required. We would like to say that this exception is allowed only in light of our long and mutually beneficial association.Yours sincerely,Mili7.卖方函电回复买方Dear: MadamThank you for you interest in our products. We hope the samples we sent you on 5 February were up to your expectations.We would like to sort out the credit formalities as soon as possible possible so that we can begin trading. Could you provide us that we can begin trading. Could you provide us with the requisite financial information so that we can open your new account immediately?Please include a recent financial statement, the name of your bank and references,together with any other relevant credit details. The information you provide will, of course, be held in the strictest confidence. We look forward to a ...
转载请注明出处51数据库 » x forword for