https://www.jiscmail.ac.uk/cgi-bin/wa-jisc.exe?A2=ind2109&L=SPACESYNTAX&O=D&P=20492

Dear all,

I hope you are doing well.

In Place Syntax Tool (PST), is there any option to calculate certain analysis (integration, choice etc.) with respect to the whole network of study?

In Depthmap there is an option of radius 'n' to calculate certain attribute with respect to the whole area of analysis. So far as I have seen PST is not taking 'n' as radius option (I tried with walking distance mode in angular integration and angular choice analysis).

My study area is about 60km by 40km (metropolitan region). I want to identify certain attributes with respect to the total area (for major routes, integration core etc.).

Any suggestion will be much helpful.

With best regards

Md. Muktadir Rahman

亲爱的大家，

我希望你做得很好。

就地语法工具 (PST)，是否有任何选项可以计算关于整个研究网络的某些分析（整合、选择等）？

在深度图中，有一个半径“n”的选项来计算关于整个分析区域的某些属性。就我所见，PST 没有将“n”作为半径选项（我尝试在角度积分和角度选择分析中使用步行距离模式）。

我的研究区域大约是 60 公里乘 40 公里（大都市区）。我想确定总面积的某些属性（对于主要路线、集成核心等）。

任何建议都会很有帮助。

最诚挚的问候

穆克塔迪尔·拉赫曼 Md. Muktadir Rahman

https://www.jiscmail.ac.uk/cgi-bin/wa-jisc.exe?A2=ind2109&L=SPACESYNTAX&O=D&P=21195

Dear Muktadir,

at sufficiently large radii the results converge into the global measure. That is you can input any large number like 999999km to basically remove the limit to the radius. Alternatively, from my experience you can set the radius to the straight line distance between furthest points of your street network or analysis area. It will should not affect the result too much, but will be slightly faster than 999999km. So in your case the longest short route in the system will be around 80 km, you can try setting the radius close to that.

Kind regards,

Egor Kotov

Spatial Data Scientist

Senior Lecturer | Research Fellow

Faculty of Urban and Regional Development

Higher School of Economics

亲爱的穆克塔迪尔，

在足够大的半径下，结果会收敛到全局度量中。也就是说，您可以输入任何大数字，例如 999999km，基本上可以消除对半径的限制。或者，根据我的经验，您可以将半径设置为街道网络或分析区域最远点之间的直线距离。它不会对结果产生太大影响，但会比 999999km 略快。因此，在您的情况下，系统中最长的短路线约为 80 公里，您可以尝试将半径设置为接近该值。

亲切的问候，

叶戈尔·科托夫

空间数据科学家

高级讲师 | 研究员

城市与区域发展学院

高等经济学院

https://www.jiscmail.ac.uk/cgi-bin/wa-jisc.exe?A2=ind2109&L=SPACESYNTAX&O=D&P=21971

Dear Muktadir,

I have not tested this in PST myself, but technically the value of radius N, or 'all to all' is equivalent to the longest shortest path of a system.

If your study area is about 60km by 40km, then I’d guess the longest shortest path is somewhere between 65km–70km.

Performing an analysis at radius 65km should hence be equivalent to radius N. You can test this yourself by running several radii e.g. 60km, 61km, 62km, etc.

At some point the result will be the same between radii–this means you have found the radius of radius N.

Best,

Kimon

亲爱的穆克塔迪尔，

我自己没有在 PST 中对此进行过测试，但从技术上讲，半径 N 的值或“全部到全部”相当于系统的 最长最短路径。

如果您的研究区域大约为 60 公里乘 40 公里，那么我猜最长最短路径在 65 公里至 70 公里之间。

因此，在半径 65 公里处执行分析应等效于半径 N。您可以通过运行多个半径（例如 60 公里、61 公里、62 公里等）来自行测试。

在某些时候，半径之间的结果将是相同的——这意味着您已经找到了半径 N 的半径。

最好的，

奇莫

https://www.jiscmail.ac.uk/cgi-bin/wa-jisc.exe?A2=ind2109&L=SPACESYNTAX&O=D&P=23457

Dear all

In the "PST with QGIS as base Workshop SSS12 Beijing 2019", the authors noted that if you leave the radius unspecified the analysis will include the whole model (map). This referred to the analysis of Attraction Distance, I wonder if this is true for all tool analysis? And whether it can be treated as a radius N?

With best regards,

Rina Magen

PhD student

亲爱的大家

在“PST with QGIS as base Workshop SSS12 Beijing 2019”中，作者指出，如果不指定半径，分析将包括整个模型（地图）。这个是指Attraction Distance的分析，不知道是不是所有工具分析都是这样？以及是否可以将其视为半径N？

最诚挚的问候，

丽娜·马根

博士生

 https://www.jiscmail.ac.uk/cgi-bin/wa-jisc.exe?A2=ind2109&L=SPACESYNTAX&O=D&P=24025

Dear Rina and all,

Thanks for the noting this in the context of attraction distance.

It would be great if this handling is also implemented for network and angular integration/betweenness.

Even though, I do not recommend the use of radius n as the analysis will inevitably be effected by edge effects (I have elaborated on this in an 2017 SSS paper on regional morphology).

At present the PST algorithm is expecting a numeric value in the radius parameter.

Hence, leaving the radius parameter empty will throw an error (" ValueError: could not convert string to float: ").

Best,

Kimon

亲爱的丽娜和大家，

感谢您在吸引力距离的背景下注意到这一点。

如果这种处理也适用于网络和角度集成/介数，那就太好了。

尽管如此，我不建议使用半径n，因为分析将不可避免地受到边缘效应的影响（我在 2017 年 SSS 关于区域形态的论文中对此进行了详细说明）。

目前，PST 算法期望半径参数中有一个数值。

因此，将半径参数留空将引发错误（“ValueError：无法将字符串转换为浮点数：”）。

最好的，

奇莫

https://www.jiscmail.ac.uk/cgi-bin/wa-jisc.exe?A2=ind2109&L=SPACESYNTAX&O=D&P=24588

Dear Dr Krenz

Thank you for the answer and helpful explanation.

(I  have read your 2017 article and relied on it in my research to find the right radii for analysis.

This is so as not to rely on radius N as representing the global level).

With best regards,

Rina Magen

PhD student

亲爱的克伦茨博士

感谢您的回答和有用的解释。

（我已经阅读了您 2017 年的文章，并在我的研究中依靠它找到了正确的半径进行分析。

这是为了不依赖半径 N 来表示全局级别）。

最诚挚的问候，

丽娜·马根

博士生