To model radiowave propagate in outdoor scenarios, we need to understand the knife edge propagation models. The knife edge model described here is a general purpose theoretic model.

I have spent some time developing the core engine that will be served as the foundation of future knife edge propagation models such as EP or Bullington.

NPM Project: https://www.npmjs.com/package/knife_edge_propagation
Test Library in Your Browser: https://npm.runkit.com/knife_edge_propagation
Github: https://github.com/DoctorLai/knife_edge_propagation

Proof of Work

doctorlai is my Github ID and you can verify that by checking my github profile page which has the same gravatar image and it shows my steemit URL. You can verify my ID via NPM profile: https://www.npmjs.com/~justyy that has a few other projects.

Sample Usage

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var knife_edge = require('knife_edge_propagation'),
    knife_edge_compute_v = knife_edge.knife_edge_compute_v,
    knife_edge_compute_pathloss = knife_edge.knife_edge_compute_pathloss,
    knife_edge_compute_pathloss_lee = knife_edge.knife_edge_compute_pathloss_lee,   
    knife_edge_compute_h = knife_edge.knife_edge_compute_h;
    
var d1 = 15;
var d2 = 25;
var h = 5;
var r = 0.002;
var v = knife_edge_compute_v(d1, d2, h, r);
var p1 = knife_edge_compute_pathloss(v);
var p2 = knife_edge_compute_pathloss_lee(v);

console.log(v);
console.log(p1);
console.log(p2);

console.log(knife_edge_compute_h(10, 100, 5, 60, 7));

Contributing

1. Fork it!
2. Create your feature branch: git checkout -b my-new-feature
3. Commit your changes: git commit -am ‘Add some feature’
4. Push to the branch: git push origin my-new-feature
5. Submit a pull request :D

Tests

I have also written a few tests so you can run via npm test

The tests are based on mocha and chai JS Unit test library:

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var should = require('chai').should(),
    knife_edge = require('../index'),
    knife_edge_compute_v = knife_edge.knife_edge_compute_v,
    knife_edge_compute_pathloss = knife_edge.knife_edge_compute_pathloss,
    knife_edge_compute_pathloss_lee = knife_edge.knife_edge_compute_pathloss_lee, 
    knife_edge_compute_h = knife_edge.knife_edge_compute_h;

describe('knife_edge_compute_v', function() {
  it('knife_edge_compute_v', function() {
    knife_edge_compute_v(15, 25, 5, 0.002).should.be.closeTo(51.6397, 1e-2);
  }); 
});

describe('knife_edge_compute_pathloss', function() {
  it('knife_edge_compute_pathloss', function() {
    knife_edge_compute_pathloss(51.6397).should.be.closeTo(47.165, 1e-2);
  });
});

describe('knife_edge_compute_pathloss_lee', function() {
  it('knife_edge_compute_pathloss_lee', function() {
    knife_edge_compute_pathloss_lee(51.6397).should.be.closeTo(47.216, 1e-2);
  });
});

describe('knife_edge_compute_h', function() {
  it('knife_edge_compute_h', function() {
    knife_edge_compute_h(10, 100, 5, 60, 7).should.be.closeTo(54.818, 1e-2);
  });
});

Computing the Heights

Image Credit: here

This is implemented as a helper function knife_edge_compute_h

Core Engine JS Source

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'use strict';

const knife_edge_compute_v = (d1, d2, h, r) => {
	return h * Math.sqrt(2 * (d1 + d2) / (r * d1 * d2));
}

const knife_edge_compute_pathloss = (v) => {
	if (v >= -0.7) {
		let t = Math.pow(v - 0.1, 2) + 1;
		return 6.9 + 20 * Math.log10(Math.sqrt(t + 1) + v - 0.1);
	}
	return 0;
}

const knife_edge_compute_pathloss_lee = (v) => {
	if (v > 2.4) return -20 * Math.log10(0.225 / v);
	if (v > 1.0) return -20 * Math.log10(0.4 - Math.sqrt(0.1184 - Math.pow(0.38 - 0.1 * v, 2)));
	if (v > 0) return -20 * Math.log10(0.5 * Math.exp(-0.95 * v));
	if (v > -0.8) return -20 * Math.log10(0.5 - 0.62 * v);
	return 0;
}

const knife_edge_compute_h = (d1, d2, h1, h2, h3) => {
	return h2 - h3 - (h1 - h3) * d2 / (d1 + d2);
}

module.exports = {
	knife_edge_compute_v, knife_edge_compute_pathloss, knife_edge_compute_pathloss_lee, knife_edge_compute_h
}

As you can see in the source code, the library exports the following methods:

• knife_edge_compute_v
• knife_edge_compute_pathloss
• knife_edge_compute_pathloss_lee
• knife_edge_compute_h

This page is synchronized from the post: NPM - Basic Knife Edge Propagation Engine

@jubi 说

Make money, and then buy villas 买别墅，我一直琢磨这事呢! !I

这话，我一直有点不确定。但是，从现在STEEM涨到8块多来说，我觉得：

Make money, and then buy a bigger house 换大房子，我一直琢磨这事呢! !I

是相对靠谱的。

STEEM大涨，有没有想起和之前 BTC 连续突破自己的记录一样，每天都给人惊喜。从今天的【CN区谁在POWER DOWN】列表来看，很多人都想变现了。

淡定，我相信它会涨到10块钱的，说不定能到100块呢？谁知道呢，说不定梦想照进现实了呢。

同步到博文: https://justyy.com/archives/5787

AD 一波，SBD比SP值钱，所以你把钱存在YY银行是很划算的，YY银行吃的是草（借的SP），挤的是奶啊（值钱的SBD）， 每日发 SBD利息，从不间断，祝股东们都在2018里赚大钱，实现财务自由啊！

通过 SP 代理工具 成为 YY银行股东，好处多多。只要代理大于10 SP给 @justyy 即可自动成为YY股东。

SteemIt 教程、机器人、在线工具和API接口
SteemIt Tutorials, Robots, Tools and APIs

近期帖子

• CN 区谁在POWER DOWN？
• Eric Learns Piano 孩子学钢琴
• 机器学习系列之：怎么样数鸡鸡？（3）分类 Clustering
• 【活动】 晒晒你的18岁 What did you look like when you were 18?
• Daily China 来了！
• 我在STEEM发文的动力
• 今天不小心给有些股东发了两次利息，就算YY股东的福利。
• SteemSQL 教程 - 我花了800多 SBD (7000多美元)买赞。

加入公众号 justyyuk 即可以实时查询 BTC, SBD, STEEM, YOYOW, LTC, ETH 等虚拟货币的价格.

• 公众号支持 实时查询 YOYOW, STEEM和SBD价格啦!
• 公众号支持 实时查询 LTC, BTC, 和ETH价格啦!
• 公众号支持 实时查询 BTS, BCH和BCG的价格啦!
  

This page is synchronized from the post: 买房这事，或许还挺靠谱的 - 记 STEEM大涨

数据来源: steemsql.com
Thank you @arcange for creating STEEMSQL!
生成时间: 2018-01-03 10:10:11 (UTC)
报告时间: 2017-12-30 10:10:11 (UTC) - 2017-12-31 10:10:11 (UTC)

2018-01-03 那些优秀可能被错过的文章

图片来源： 每日BING桌面壁纸 @superbing
| | 作者 Author| 文章 Post|
|———-|:————-:|:——|
| 1 | @travelgirl | City Scape Photography Contest - Eiffel Tower @ Paris, France - 城市攝影比賽 - 巴黎鐵塔 @ 巴黎，法國 |
| 2 | @fundurian | Cryptocurrency that want to take down Ethereum, 想打倒Ethereum的竞争者 |
| 3 | @susanli3769 | 2018 狗年贺卡 Happy New Year to everyone |
| 4 | @winniex | 一觉醒来 |
| 5 | @pakyeechan | 新年快樂 Happy New Year Steemians ! |
| 6 | @ygern | 2017，最後一夜。 |
| 7 | @angelina6688 | Gold shrimp 黄金虾 |
| 8 | @jubi | Glitchskier: this game is so funny /复古手游之代码大战 |
| 9 | @guyverckw | New Year’s Day is also Birthday! 生日就在新的一年 |
| 10 | @kenchung | 祝大家新年快樂！ Happy New Year! |
| 12 | @tumutanzi | Seven Day, Black & White Challenge: Day 4 by @tumutanzi |

本列表支持黑名单用于过滤经常发水文的ID，欢迎 report@justyy.com 举报。

2018-01-03 Daily Top Authors in [CN] (Last 7 Days) 每日cn社区之 过去7天潜在收益排行榜

The following is the list of top 30 daily authors in [CN] in the last 7 days sorted by potential payout. See the SQL for more details.
这是根据这篇的SQL - 经少量修改和调整统计出过去7天作者的潜在收益排行。
| 排名 Rank| 作者 Author| 发贴数 Posts| 点赞数 Votes| 潜在收益 Pending Payout| 平均每贴收益 Average Pending Payout Per Post|
|:–|:–|:–|:–|:–|:–|
| 1| @oflyhigh | 14 | 2895 | 1984.43 |141.75 |
| 2| @chinadaily | 31 | 1621 | 1965.89 |63.42 |
| 3| @deanliu | 11 | 1509 | 1190.10 |108.19 |
| 4| @rea | 5 | 985 | 1039.03 |207.81 |
| 5| @rivalhw | 13 | 1344 | 956.33 |73.56 |
| 6| @sweetsssj | 1 | 1933 | 719.86 |719.86 |
| 7| @helene | 7 | 1008 | 679.87 |97.12 |
| 8| @catwomanteresa | 6 | 540 | 554.93 |92.49 |
| 9| @ace108 | 31 | 2230 | 540.13 |17.42 |
| 10| @blackbunny | 7 | 494 | 530.18 |75.74 |
| 11| @magicmonk | 9 | 924 | 458.44 |50.94 |
| 12| @stacee | 12 | 820 | 446.08 |37.17 |
| 13| @justyy | 29 | 1412 | 400.04 |13.79 |
| 14| @bxt | 17 | 673 | 392.09 |23.06 |
| 15| @jubi | 24 | 847 | 369.99 |15.42 |
| 16| @htliao | 7 | 906 | 361.50 |51.64 |
| 17| @joythewanderer | 8 | 823 | 300.97 |37.62 |
| 18| @darksaint | 13 | 109 | 278.56 |21.43 |
| 19| @twinkledrop | 7 | 309 | 263.98 |37.71 |
| 20| @lawrenceho84 | 10 | 546 | 261.17 |26.12 |
| 21| @victory622 | 13 | 375 | 256.60 |19.74 |
| 22| @susanli3769 | 22 | 649 | 248.01 |11.27 |
| 23| @kimzwarch | 12 | 314 | 234.28 |19.52 |
| 24| @vandadream | 13 | 346 | 208.69 |16.05 |
| 25| @randyw | 7 | 151 | 201.87 |28.84 |
| 26| @rosatravels | 14 | 283 | 190.41 |13.60 |
| 27| @mcw | 7 | 1005 | 181.03 |25.86 |
| 28| @krischy | 5 | 623 | 165.43 |33.09 |
| 29| @aaronli | 7 | 978 | 165.15 |23.59 |
| 30| @nicolemoker | 5 | 737 | 160.26 |32.05 |

以上收益包括75%的作者收益(Author Rewards)和25%的点赞收益(Curation Rewards)。
@dailystats 提供过去7天全网潜在收益前30名的排名
check @dailystats for top 30 daily authors in the last 7 days sorted by potential payout

CN 区优质内容点赞机器人每天可能会为这30名作者点赞！
CN Good-Content-Bot may upvote these authors every day!

2018-01-03 CN区成员谁在 POWER DOWN? (List of CN Members Power Down)

一共正在DOWN的SP总量为：60597.31 Steem Power.

近期机器人点赞记录 Recent Quality-Content-Upvote-Bot Upvoting History

这个机器人很善良，只想激励CN社区产生更多的优质内容。当然别忘记了，我本人人工也是会对未上榜的优质作者进行点赞的哟~

这个报告的年龄为: 131天。
为什么要有这个报告？
欢迎 @justyy 如果您有好的建议或者想看哪些榜单却找不到。

• CN 中文区每日【YY银行利息统计】【点赞年化率】
• CN 中文区每日【活跃统计数据】【财富总值】

@justyy 是 https://justyy.com 的博主，写些帖子挣些小钱养家糊口。@justyy 也是CN 区的点赞机器人，对优质内容进行点赞，只要代理给 @justyy 每天收利息(年化率 5%)并且能获得一次相应至少2倍的点赞，可以认为是VP 200%+。加入计划最低代理10SP。CN 区的大鱼 @htliao 也加入了计划（代理了 530 SP）。

1. CN 区最低保障系统 上线了!
2. CN 区低保计划（鼓励新人）真的适合你么？
3. CN 区优质内容点赞机器人上线了!
4. 点赞机器人每日点赞记录整合到每日报表中！
5. 虽然不挣钱，但是CN区低保计划还会继续下去
6. cnbuddy 和 YY 银行的区别，哪个更适合你？

YY银行有 83位股东，一共股权总量为 18238.2 SP

查询谁都参于了也可以用这个在线工具: Steemit 查看谁委派代理给你Steem Power？。
|Delegator| Steem Power| Vests| DateTime|
|:–|:–|:–|:–|
| @davidmendel |3004.59|6156208.05|2017-12-03 20:15:09|
| @bobdos |3001.49|6149856.95|2017-12-24 09:52:00|
| @eduter |925.72|1896743.76|2017-11-06 03:57:36|
| @wongshiying |774.89|1587698.86|2017-12-18 08:45:33|
| @mrpointp |600.4|1230175.09|2017-12-21 01:18:39|
| @htliao |532.48|1091019.80|2017-10-03 12:00:48|
| @daydayup |501.97|1028505.54|2017-10-17 21:39:27|
| @fundurian |501.28|1027100.59|2017-11-13 12:19:12|
| @bigbigfish |500.35|1025193.45|2017-12-20 02:57:39|
| @magicmonk |500.26|1025010.00|2017-12-31 09:50:33|
| @zhouyagen |456.06|934435.22|2017-11-18 05:52:12|
| @timknip |350.4|717941.78|2017-12-11 14:38:21|
| @zsilence |301.56|617872.78|2017-09-23 16:04:45|
| @mrspointm |301.48|617714.93|2017-09-28 14:07:18|
| @luneknight |300.83|616380.50|2017-11-09 17:09:45|
| @shengjian |300.72|616162.83|2017-11-16 14:28:48|
| @oldman28 |300.63|615966.94|2017-11-22 19:46:18|
| @stabilowl |300.62|615948.17|2017-11-23 10:04:21|
| @jiayanglai |300.08|614842.63|2017-12-29 02:31:36|
| @berlin1997 |201.0|411835.88|2017-09-27 08:55:06|
| @susanli3769 |200.79|411400.20|2017-10-17 23:56:57|
| @mangoanddaddy |200.43|410677.78|2017-11-21 05:54:18|
| @vandadream |200.25|410292.30|2017-12-09 16:27:51|
| @bonjovis |200.22|410242.67|2017-12-12 01:59:27|
| @windowglass |200.01|409802.07|2018-01-02 16:37:06|
| @liangfengyouren |130.41|267199.31|2017-11-02 08:44:12|
| @kangnajiang |117.52|240787.09|2017-10-08 10:12:12|
| @zhijun |100.96|206853.00|2017-09-19 03:18:57|
| @jessicameng |100.54|205993.57|2017-09-20 09:14:24|
| @fr3eze |100.51|205931.08|2017-09-26 03:17:24|
| @jiangchen |100.49|205895.44|2017-09-29 11:36:09|
| @drunkevil |100.48|205885.32|2017-09-30 10:23:51|
| @joythewanderer |100.4|205714.60|2017-10-16 14:51:15|
| @shenchensucc |100.38|205666.15|2017-10-21 05:12:21|
| @nationalpark |100.28|205476.85|2017-11-08 03:15:06|
| @aaronli |100.28|205459.25|2017-11-09 19:14:57|
| @lixing |100.26|205422.08|2017-11-13 07:50:27|
| @heyeshuang |100.22|205345.07|2017-11-20 15:45:54|
| @nuagnorab |100.17|205243.45|2017-11-30 08:22:30|
| @kimzwarch |100.13|205157.12|2017-12-08 15:06:21|
| @moobear |100.08|205061.25|2017-12-17 22:12:15|
| @wang-peilin |100.05|205005.20|2017-12-23 09:47:36|
| @lymichale |100.03|204957.31|2017-12-28 03:26:51|
| @ety001 |100.0|204901.79|2018-01-02 14:49:00|
| @rmb |80.07|164066.73|2017-12-15 18:27:39|
| @antone |80.04|163993.93|2017-12-24 16:32:00|
| @redtea |70.17|143768.53|2017-11-16 23:37:12|
| @xyj |70.08|143588.38|2017-12-11 14:32:51|
| @monkeyplayfire |70.08|143587.76|2017-12-11 16:36:12|
| @xiaoshancun |68.22|139787.01|2017-10-30 09:51:18|
| @mumingduozi |60.48|123928.00|2017-09-19 00:25:12|
| @yellowbird |60.01|122966.85|2017-12-29 09:07:00|
| @liumei |50.26|102983.93|2017-09-22 17:35:12|
| @tvb |50.24|102943.21|2017-09-30 07:54:27|
| @veronicazhu |50.23|102913.15|2017-10-06 00:26:30|
| @waiyee422 |50.02|102477.92|2017-12-28 06:55:36|
| @angelina6688 |50.01|102467.98|2017-12-30 05:54:24|
| @bigcat |42.1|86268.13|2017-11-15 09:29:03|
| @speeding |40.16|82280.25|2017-10-17 22:45:06|
| @raywang |30.15|61779.27|2017-09-26 03:40:09|
| @jychbetter |30.06|61598.33|2017-11-22 07:20:24|
| @renzhichu |30.02|61510.38|2017-12-20 12:31:12|
| @tranquilpoem |29.04|59492.92|2017-12-09 12:10:54|
| @al2ping |25.02|51257.35|2017-12-21 00:46:18|
| @hopsken |25.0|51223.74|2018-01-03 06:59:57|
| @feng1925 |20.11|41198.84|2017-09-20 07:52:30|
| @jiba |20.07|41120.90|2017-10-27 01:25:36|
| @techlee |20.06|41098.79|2017-11-06 12:28:48|
| @yanel |20.05|41080.66|2017-11-15 02:42:27|
| @juanyao |20.03|41038.68|2017-12-05 03:22:12|
| @pptx |20.02|41010.70|2017-12-18 16:21:21|
| @wlcpu |20.01|41005.90|2017-12-21 00:34:42|
| @lovemyson |18.01|36894.30|2017-12-27 01:26:24|
| @towardsthesun |15.0|30742.26|2017-12-29 00:29:30|
| @chenhb1968 |11.01|22549.46|2017-12-24 10:15:15|
| @nahaha |10.51|21528.04|2017-12-21 01:50:48|
| @wangwenjing |10.05|20598.79|2017-09-20 21:35:18|
| @willwangfeng |10.04|20576.13|2017-10-12 04:24:57|
| @winniex |10.03|20547.82|2017-11-08 00:07:12|
| @zizizhuji |10.03|20541.39|2017-11-14 02:23:18|
| @liuboya |10.01|20508.96|2017-12-15 04:00:21|
| @coindzs |10.01|20502.83|2017-12-21 03:19:33|
| @sphenix |10.0|20498.31|2017-12-25 14:37:48|
一共 18238.2 SP, 37368910.21 VESTS。

通过 SP 代理工具 成为 YY银行股东，好处多多。只要代理大于10 SP给 @justyy 即可自动成为YY股东。

SteemIt 教程、机器人、在线工具和API接口
SteemIt Tutorials, Robots, Tools and APIs
AD 一波，最近SBD涨到8块钱，1 SBD 比 STEEM值钱多了，所以你把钱存在YY银行是很划算的，YY银行吃的是草（借的SP），挤的是奶啊（SBD利息），每日发 SBD利息，从不间断。提前祝YY股东们圣诞快乐，新年快乐，股东们都在2018里赚大钱，实现财务自由啊！

加入公众号 justyyuk 即可以实时查询 BTC, SBD, STEEM, YOYOW, LTC, ETH 等虚拟货币的价格.

• 公众号支持 实时查询 YOYOW, STEEM和SBD价格啦!
• 公众号支持 实时查询 LTC, BTC, 和ETH价格啦!
• 公众号支持 实时查询 BTS, BCH和BCG的价格啦!
  

This page is synchronized from the post: Daily #CN Updates CN社区【七天收益排行榜】【CN区谁在POWER DOWN？】【优秀被错过的文章】【YY银行股东名单】(2018-01-03)

我们知道 steemdown.com 可以看哪些大鱼在POWER DOWN。如果我们想了解一下CN成员谁在POWER DOWN就比较难办了，不过，经过一些努力，这些数据将会集成到每日报表中，比如：

Daily #CN Updates CN社区【七天收益排行榜】【CN区谁在POWER DOWN？】【优秀被错过的文章】【YY银行股东名单】(2018-01-02)

每日报表会添加以下数据（刚刚新鲜出炉的，按DOWN 的SP排序）：

最后面 Week 就表示在DOWN的第几周。看到小伙伴们都在DOWN了，你也赶紧DOWN吧

2018-01-03 CN区成员谁在 POWER DOWN? (List of CN Members Power Down)

想加入CN区成员？ 给我邮件 wexin@justyy.com （注明你的STEEM ID）

AD 一波，SBD比SP值钱，所以你把钱存在YY银行是很划算的，YY银行吃的是草（借的SP），挤的是奶啊（值钱的SBD）， 每日发 SBD利息，从不间断，提前祝YY股东们圣诞快乐，新年快乐，股东们都在2018里赚大钱，实现财务自由啊！

通过 SP 代理工具 成为 YY银行股东，好处多多。只要代理大于10 SP给 @justyy 即可自动成为YY股东。

SteemIt 教程、机器人、在线工具和API接口
SteemIt Tutorials, Robots, Tools and APIs

近期帖子

• Eric Learns Piano 孩子学钢琴
• 机器学习系列之：怎么样数鸡鸡？（3）分类 Clustering
• 【活动】 晒晒你的18岁 What did you look like when you were 18?
• Daily China 来了！
• 我在STEEM发文的动力
• 今天不小心给有些股东发了两次利息，就算YY股东的福利。
• SteemSQL 教程 - 我花了800多 SBD (7000多美元)买赞。
• 愉快的 Boxing Day | Happy Boxing Day (Photography)
• 2017 年，我的热门帖子 My Top Posts in 2017!
• 在英国的第13个圣诞节 Merry Christmas 2017! | 月旦评

加入公众号 justyyuk 即可以实时查询 BTC, SBD, STEEM, YOYOW, LTC, ETH 等虚拟货币的价格.

• 公众号支持 实时查询 YOYOW, STEEM和SBD价格啦!
• 公众号支持 实时查询 LTC, BTC, 和ETH价格啦!
• 公众号支持 实时查询 BTS, BCH和BCG的价格啦!
  

This page is synchronized from the post: CN 区谁在POWER DOWN？

I have been studying the official Steem Python library at https://github.com/steemit/steem-python and IMHO it lacks of checking if any given ID is muted by the Account. Simply put, the has_muted is useful in checking if current account has muted a given ID, and unmute will simply unmute the ID. These two can be described by the following:

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id = Account("justyy")
if id.has_muted("someone"):
   id.unmute("someone")

Similarly, is_muted_by checks the other way around and mute will mute the given ID:

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id = Account("justyy")
if id.is_muted_by("someone"):
    id.mute("someone")

These four methods should be a great add-on features to the steem python library!

This page is synchronized from the post: Suggestion: Add has_muted, is_muted_by, mute, unmute methods in Steem Python Library

Github: https://github.com/DoctorLai/freespace
NPM Project: https://www.npmjs.com/package/wireless_pathloss
Test wireless_pathloss in browser: https://npm.runkit.com/wireless_pathloss

Introduction

This is a NPM Js Library that provides the free space calculation in the wireless field.

Install the wireless_pathloss

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npm install wireless_pathloss

Sample Usage

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var wireless = require('wireless_pathloss');
wireless.wireless.Antenna(0, 0, 300);
wireless.wireless.SetFrequency(947);
console.log(wireless.wireless.GetPathLoss(0, 0, 0));
console.log(wireless.freespace(2400, 300));
console.log(wireless.freespace_k1k2k3(30, 2, 0, 100));

This will output:

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81.51942467445872
89.59664992862537
34

Exposed Methods:

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module.exports = {
	freespace, freespace_k1k2k3, wireless
}

where wireless is an object with methods:

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var wireless = (function(){
	// default WIFI 2.4 GHz
	var frequency = 2400;
	// default Antenna (0, 0, 0)
	var _x = 0;
	var _y = 0;
	var _z = 0;
	
	function setAntenna(ax, ay, az) {
		_x = ax;
		_y = ay;
		_z = az;
	}
	
	function setFreq(f) {
		frequency = f;
	}

	function getFreq() {
		return frequency;
	}

	function getDist(x1, y1, z1, x2, y2, z2) {
		return Math.sqrt((x1 - x2) * (x1 - x2) + (y1 - y2) * (y1 - y2) + (z1 - z2) * (z1 - z2));
	}

	var getPathLoss = function(x, y, z) {
		return freespace(frequency, getDist(x, y, z, _x, _y, _z));
	}

	return {
		Antenna: function(x, y, z) {
			setAntenna(x, y, z);
		},

		SetFrequency: function(f) {
			setFreq(f);
		},

		GetFrequency: function() {
			return getFreq();
		},

		GetDist: function(x, y, z) {
			return getDist(x, y, z, _x, _y, _z);
		},

		GetPathLoss: function(x, y, z) {
			return getPathLoss(x, y, z);
		}
	};
})();

Tests

use npm test to run tests

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var should = require('chai').should(),
    wireless_pathloss = require('../index'),
    wireless = wireless_pathloss.wireless,
    freespace = wireless_pathloss.freespace,
    freespace_k1k2k3 = wireless_pathloss.freespace_k1k2k3;

describe('wireless', function() {
  it('wireless', function() {
    wireless.Antenna(0, 0, 300);
    wireless.SetFrequency(947);
    wireless.GetPathLoss(0, 0, 0).should.be.closeTo(81.5194, 1e-2);
  }); 
});

describe('freespace', function() {
  it('freespace', function() {
    freespace(2400, 300).should.be.closeTo(89.5966, 1e-2);
  });
});

describe('freespace_k1k2k3', function() {
  it('freespace_k1k2k3', function() {
    freespace_k1k2k3(30, 2, 0, 100).should.be.closeTo(34, 1e-2);
  });
});

Contributing

1. Fork it!
2. Create your feature branch: git checkout -b my-new-feature
3. Commit your changes: git commit -am ‘Add some feature’
4. Push to the branch: git push origin my-new-feature
5. Submit a pull request :D

This page is synchronized from the post: NPM Library: wireless_pathloss - The Free Space Propagation Calculator