[datameet] Natural_earth world countries modified as per SOI India Map

[Naraina Damle]

Hello, 

I have modified the Natural Earth Countries and Lakes Layer as per the SOI 
Map.

Link is here

https://drive.google.com/open?id=1vhItOq3oO25o6lq__cIVhsx2afDgpXdd


The neighbouring country Boundaries have been modified.

I would people to have a look and check if there are any errors.



Regards

Naraina Damle

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[datameet] Fwd: Talk on Technology and Politics - NREGA @ IIITB tomorrow

[Rajesh D Hanbal]

Dear Community, 

This talk might be of interest to Open Data enthusiasts especially because 
it will touch upon interesting attempts to re-represent government data to 
empower grassroots organizations and communities.  

Thanks,
Rajesh


On Tuesday, April 16, 2019 at 6:59:21 PM UTC+5:30, Rajesh D Hanbal wrote:
>
>
>
> Dear Researchers/Activists, 
>
> You are welcome to attend a talk on titled "*Technocracy as the veil for 
> lack of political will" *by Rajendran Narayanan at IIITB tomorrow at 4 
> PM. More details below. 
>
> Thanks,
> Rajesh
>
>
>
>
>
>
> *The Centre for Information Technology and Public Policy (CITAPP)*
>
> *International Institute of Information Technology Bangalore (IIITB)*
>
>  
>
> invites you to a talk titled
>
>  
>
> *Technocracy as the veil for lack of political will: In the context of 
> NREGA*
>
> by
>
>  
>
> * Rajendran Narayanan*
>
> *Assistant Professor, Azim Premji University*
>
>  
>
> *4:00 pm - 5:30 pm on 17th April 2019 (Wednesday)*
>
> Venue:* Room #310, IIITB campus*
>
> *26/C, Electronic City, Hosur Road, Bangalore*
>
>
> * About the talk:*
>
> The Right to Information (RTI) has been a landmark law to increase 
> transparency and accountability of the government. In this regard, Social 
> Audits have been a powerful mechanism of monitoring and participation for 
> the marginalised sections to know their rights and entitlements and act 
> based on that knowledge. Social audits entail culling out and presenting 
> relevant information in a manner that is most useful to people 
> participating in programmes such as the National Rural Employment Guarantee 
> Act (NREGA). The information can then be used to conduct public hearings 
> leading to increased democratic engagement and participation. Rajendran is 
> a founder member of a collective of researchers and activists called LibTech 
> India . LibTech works with an array of civil society 
> organisations across several states in designing and developing "bottom-up" 
> Janata Information Systems (JIS). Such information can then be used for 
> continuous monitoring of government programmes and social audits. LibTech 
> India has also been active in various national campaigns as the National 
> Campaign for People’s Right to Information (NCPRI), the Right to Food 
> Campaign, NREGA Sangharsh Morcha and the People’s Action for Employment 
> Guarantee.
>
>  
>
> *Speaker Bio**:* Rajendran is an Assistant Professor in the School of 
> Liberal Studies, Azim Premji University, Bangalore. After completing his 
> Ph.D. in statistics from Cornell University, he has held teaching and 
> research positions at the Indian Statistical Institute, Kolkata, Cornell 
> University, Ithaca and Ashoka University, Sonepat. In his doctoral work, he 
> explored theoretical questions pertaining to eigenvalues of random matrices 
> and shrinkage estimation in constrained regression problems. He has since 
> gradually migrated to the real world and engages in ‘Research for Action’ 
> in questions pertaining to transparency, accountability, and human rights.
>
> To know more about CITAPP visit *http://citapp.iiitb.ac.in/ 
> * and to explore M.Sc. (Digital Society) 
> programme visit 
> *http://citapp.iiitb.ac.in/academic-programmes/m-sc-digital-society/ 
> *
>

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Re: [datameet] Re: Correct CRS for datameet maps

[Nikhil VJ]

Hi Devdatta

Thanks a ton for the correction! I'll use EPSG:7755 for distance related
work here on out.

--
Cheers,
Nikhil VJ, Pune, India
http://nikhilvj.co.in


On Tue, Apr 16, 2019 at 11:56 AM Devdatta Tengshe 
wrote:

> HI Ashim, & others,
>
> Coordinate systems, and their area of applicability is an abstruse topic,
> and one that has many complicated things to consider. So what I'm saying
> here is a user-friendly summary.
>
>
>- The data in our Repository is in WGS-84 Lat/long, which has the EPSG
>code 4326.
>- You seem to be projecting it to ESPG: 2154, which is coordinate
>system applicable in France.( http://epsg.io/2154)  I can't see a
>Valid reason for doing this.
>- If you need to project to a projected Coordinate System,(Maybe for
>calculating areas & distances) you should use EPSG:7755, (
>http://epsg.io/7755) which is the one defined in NNRMS standards, and
>is used by many Government Organizations, like ISRO, NURM etc.
>- I generally* won't recommend* projecting to EPSG:3857, which is the
>webmercator projection, since it has several issues. *You should never
>measure areas or distances using this projection*.
>
>
>
>
> Regards,
> Devdatta
>
>
> On Tue, Apr 16, 2019 at 11:42 AM Nikhil VJ  wrote:
>
>> Hi Ashim,
>>
>> Pls provide the exact link of what you're referring - this stuff is never
>> as much on the top of people's minds as we assume it to be.
>> Do try loading your shapefiles on other tools and check there :
>> mapshaper.org is a site that does a lot of quick, cool things with
>> shapefiles; QGIS is a software that does everything with shapefiles. Both
>> are free and open source.
>>
>> The latter will help you re-save the shapefile into any CRS you want.
>> Right-click the layer > Save As (or "Export") and remember to choose your
>> preferred CRS in the dropdown.
>>
>> Can you give background on what this CRS : *2154* : is and why you want
>> to transform to that? Because I've only come across two main CRS's both
>> being under the "WSG 84" category :
>> - EPSG 4326 : this makes everything in latitude longitude
>> - EPSG 3857 : this makes everything in meters from the equator (I think)
>> and we need to get the data in this format when we want to do things in
>> physical distance terms like making a 1km distance buffer or measuring areas
>>
>> I haven't learned GIS stuff from theory, I just use it, so don't know
>> more details about CRS. I do understand that the dizzying multitude of
>> CRS's out there are so because apparently GIS folks like to re-orient the
>> center of the world (geometrically speaking) to where their data is to
>> ensure least distortion of their shapes in the rendering. When I come
>> across anything that's in a non-standard CRS, my first move is to transform
>> it to either lat-longs (4326) or meters (3857).
>>
>> Regards
>> Nikhil VJ
>>
>>
>> On Monday, April 15, 2019 at 1:57:20 PM UTC+5:30, Ashim wrote:
>>>
>>> Dear All,
>>>
>>> I am referring to 2011_Dist. * set of shapefile. (District level
>>> shapefiles).
>>>
>>> When I read them as simple features in R, ( like this )
>>>
>>> map <- st_read("2011_Dist.shp") %>% st_as_sf()
>>>
>>> ( it's unprojected because it says 4326 in the epsg when I read the
>>> above )
>>>
>>> plot(map$geometry)
>>>
>>> it looks OK.
>>>
>>> But when I do :
>>>
>>> map <- st_read("2011_Dist.shp") %>% st_as_sf() %>% st_transform(crs=
>>> 2154)
>>>
>>> plot(map$geometry)
>>>
>>> the map is TILTED.
>>>
>>> What is the correct projection to use for this dataset? Please clarify.
>>>
>>> Best Regards,
>>> Ashim
>>>
>> --
>> Datameet is a community of Data Science enthusiasts in India. Know more
>> about us by visiting http://datameet.org
>> ---
>> You received this message because you are subscribed to the Google Groups
>> "datameet" group.
>> To unsubscribe from this group and stop receiving emails from it, send an
>> email to datameet+unsubscr...@googlegroups.com.
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>>
> --
> Datameet is a community of Data Science enthusiasts in India. Know more
> about us by visiting http://datameet.org
> ---
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>

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Re: [datameet] Re: Correct CRS for datameet maps

[Ashim Kapoor]

Dear All,

I have a small query on similar lines. When do we use  UNPROJECTED maps ? I
understand that to go from 3D to 2D we need a projection. When is it
reasonable to use an unprojected map?

Many thanks,
Ashim

On Tue, Apr 16, 2019 at 12:12 PM Ashim Kapoor  wrote:

> Dear Devdatta and Nikhil,
>
> I attended a R GIS school where the teachers were from France and they
> were using CRS 2154. They told us that they were not familiar with the CRS
> for Indian maps.
>
> I used 2154 thinking that it would not make much  of a difference, but I
> was wrong. My apologies for the confusion. When I used that on Indian (
> datameet ) shapefiles,I got this : map1.png ( see attachment )
>
> I have also attached the R code to create these maps from the Datameet
> District level ( 2011 ) shapefiles. I have created map2.png and map3.png
> from crs = 3857 / 7755 respectively.
>
> I also found this :
> https://epsg.io/?q=india
>
> Which is confusing because many CRS are there for India. Why do we have so
> many choices of CRS for India ?
>
> I guess for the time being I will use 7755.
>
> Many thanks to Devdatta and Nikhil for their help.
> Best Regards,
> Ashim
>
>
>
> On Tue, Apr 16, 2019 at 11:42 AM Nikhil VJ  wrote:
>
>> Hi Ashim,
>>
>> Pls provide the exact link of what you're referring - this stuff is never
>> as much on the top of people's minds as we assume it to be.
>> Do try loading your shapefiles on other tools and check there :
>> mapshaper.org is a site that does a lot of quick, cool things with
>> shapefiles; QGIS is a software that does everything with shapefiles. Both
>> are free and open source.
>>
>> The latter will help you re-save the shapefile into any CRS you want.
>> Right-click the layer > Save As (or "Export") and remember to choose your
>> preferred CRS in the dropdown.
>>
>> Can you give background on what this CRS : *2154* : is and why you want
>> to transform to that? Because I've only come across two main CRS's both
>> being under the "WSG 84" category :
>> - EPSG 4326 : this makes everything in latitude longitude
>> - EPSG 3857 : this makes everything in meters from the equator (I think)
>> and we need to get the data in this format when we want to do things in
>> physical distance terms like making a 1km distance buffer or measuring areas
>>
>> I haven't learned GIS stuff from theory, I just use it, so don't know
>> more details about CRS. I do understand that the dizzying multitude of
>> CRS's out there are so because apparently GIS folks like to re-orient the
>> center of the world (geometrically speaking) to where their data is to
>> ensure least distortion of their shapes in the rendering. When I come
>> across anything that's in a non-standard CRS, my first move is to transform
>> it to either lat-longs (4326) or meters (3857).
>>
>> Regards
>> Nikhil VJ
>>
>>
>> On Monday, April 15, 2019 at 1:57:20 PM UTC+5:30, Ashim wrote:
>>>
>>> Dear All,
>>>
>>> I am referring to 2011_Dist. * set of shapefile. (District level
>>> shapefiles).
>>>
>>> When I read them as simple features in R, ( like this )
>>>
>>> map <- st_read("2011_Dist.shp") %>% st_as_sf()
>>>
>>> ( it's unprojected because it says 4326 in the epsg when I read the
>>> above )
>>>
>>> plot(map$geometry)
>>>
>>> it looks OK.
>>>
>>> But when I do :
>>>
>>> map <- st_read("2011_Dist.shp") %>% st_as_sf() %>% st_transform(crs=
>>> 2154)
>>>
>>> plot(map$geometry)
>>>
>>> the map is TILTED.
>>>
>>> What is the correct projection to use for this dataset? Please clarify.
>>>
>>> Best Regards,
>>> Ashim
>>>
>> --
>> Datameet is a community of Data Science enthusiasts in India. Know more
>> about us by visiting http://datameet.org
>> ---
>> You received this message because you are subscribed to the Google Groups
>> "datameet" group.
>> To unsubscribe from this group and stop receiving emails from it, send an
>> email to datameet+unsubscr...@googlegroups.com.
>> For more options, visit https://groups.google.com/d/optout.
>>
>

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Re: [datameet] Mapping of Hyderabad Bus Stops and Routes

[Nikhil VJ]

Hi Folks,

TL;DR : Exciting data challenges at bottom!

[image: payanam-map.jpg]

Following up here after a lot has happened!

We've done quite a bit of mapping and are at a point now where the 
remaining unmapped portions can use some attention from people who know 
Hyderabad like the back of their hand.

So reaching out to such folks: Inviting you to review the routes on our 
work-site: https://server.nikhilvj.co.in/payanam/ .

There's a bunch of pages - please use the top menu to navigate. (and please 
see the site from a wide screen and not a cell phone! It's a work-site! :P 
). I won't get into explaining it all here but will advise the curious to 
play around like a naughty kid and click everything once or twice before 
reaching back with queries.

If you know where some of these missing stops are supposed to be, or if a 
route has something entered wrong, then please let me know.  Do check out 
the Map page where you can have a birds-eye view. You can contact me on 
nikhil.js [at] gmail.com or 9665831250.

-

DATA CHALLENGES

We have some exciting challenges for the data, programming and GIS whizzes 
out there (no need to be from Hyd for this):

- Visualize our metrics over time 
: https://server.nikhilvj.co.in/payanam/reports/stats.json : snazziest one 
gets officially embedded and featured, and don't give me simple stuff : I did 
that already 

.

- Find common patterns: If each trip is represented as a word/string with 
each unique stop being three letters (26^3 - who knew you could encode so 
much in 3 letters!), then can you detect the common substrings? Data: 
https://server.nikhilvj.co.in/payanam/reports/route_patterns.csv
Expanding on this a bit: We want to know which routes have A > B > C > D 
pattern in common, in that order and not jumbled up. And don't bother with 
permutations-combinations : I ran a script doing that for 11 days straight 
on a server and didn't get far because there's gazillions of common 
patterns in 4000+ stops!

- Detect all clusters of stops from a large data-bank that are located just 
X meters from each other. (contact for getting set up with the data)

- Given a route of stops and a data-bank of existing stops, find the stops 
that might also be on that route. (contact for getting set up with the data)

- Generate on-road paths of the routes using the stops as waypoints. The 
resulting data must be copyright-free. (contact for getting set up with the 
data)

-

PS: For those reading this thread first time : This is a joint project by 
World Resources Institute and Telangana Open Data Portal - interns may 
apply for any of the above mentioned tasks, but note that it'll be in this 
"just take it and do it" challenge format and not spoon-feeding / teaching 
format (Dude if I already knew, I'd finish this stuff myself!)


Regards
Nikhil VJ, Pune, India



On Sunday, January 6, 2019 at 10:13:14 AM UTC+5:30, Nikhil VJ wrote:
>
> Hi Friends, 
>
> We had a great mapping session yesterday. Most valuable was the tacit 
> local information of the participants.
> We're changing venue and timings today :
>
> 6th Jan : continuation of Hyderabad Bus Routes mapping and discussion 
> about project
> 3rd Floor, Abhyaas (opp JNTU gate, behind ICICI bank)
> 1pm to 6pm (break around 3pm)
>
>
> Regards
> Nikhil VJ
>
> On Friday, January 4, 2019 at 3:27:32 PM UTC+5:30, Nikhil VJ wrote:
>>
>> Hi Folks,
>>
>> Apologies for the late post, but please share this with your friends in 
>> Hyderabad. We're conducting a Mapathon for mapping Hyderabad's Bus Routes.
>>
>> 5th, 6th Jan 2019, JNTU College, 10am to 6pm. Participants can also come 
>> on just one of the days.
>>
>>
>> 
>>
>> Direct link to poster: https://i.imgur.com/7dvSfIt.jpg
>>
>>
>> Regards
>> Nikhil VJ, Pune, India
>>
>>
>> On Tuesday, December 11, 2018 at 4:39:34 PM UTC+5:30, Nikhil VJ wrote:
>>>
>>> Hi Srihari,
>>>
>>> Session was good! Our main purpose was to announce about the project and 
>>> invite the larger GIS community in Hyderabad to come in and get involved, 
>>> share ideas or even take up some tasks if they feel inclined. So that 
>>> invite remains open - pls contact me on me [at] nikhilvj.co.in if 
>>> anyone wants to get involved and is ready for grunt work (I prefer 
>>> Hyderabad-based folks because you'll need to know those places, but there 
>>> are opportunities for folks outside too).
>>>
>>> I'm very excited about the possibility of detecting common patterns 
>>> between the routes, suggested by one of the participants whose group works 
>>> with Random Forest. If we can bring common pattern detection and editing to 
>>> routes management it'll mean a major time-saving in editing routes. 
>>> (Example use case: one more stop is added between two existing ones. The 
>>> change should get 

Re: [datameet] Re: Correct CRS for datameet maps

[Ashim Kapoor]

Dear Devdatta and Nikhil,

I attended a R GIS school where the teachers were from France and they were
using CRS 2154. They told us that they were not familiar with the CRS for
Indian maps.

I used 2154 thinking that it would not make much  of a difference, but I
was wrong. My apologies for the confusion. When I used that on Indian (
datameet ) shapefiles,I got this : map1.png ( see attachment )

I have also attached the R code to create these maps from the Datameet
District level ( 2011 ) shapefiles. I have created map2.png and map3.png
from crs = 3857 / 7755 respectively.

I also found this :
https://epsg.io/?q=india

Which is confusing because many CRS are there for India. Why do we have so
many choices of CRS for India ?

I guess for the time being I will use 7755.

Many thanks to Devdatta and Nikhil for their help.
Best Regards,
Ashim



On Tue, Apr 16, 2019 at 11:42 AM Nikhil VJ  wrote:

> Hi Ashim,
>
> Pls provide the exact link of what you're referring - this stuff is never
> as much on the top of people's minds as we assume it to be.
> Do try loading your shapefiles on other tools and check there :
> mapshaper.org is a site that does a lot of quick, cool things with
> shapefiles; QGIS is a software that does everything with shapefiles. Both
> are free and open source.
>
> The latter will help you re-save the shapefile into any CRS you want.
> Right-click the layer > Save As (or "Export") and remember to choose your
> preferred CRS in the dropdown.
>
> Can you give background on what this CRS : *2154* : is and why you want
> to transform to that? Because I've only come across two main CRS's both
> being under the "WSG 84" category :
> - EPSG 4326 : this makes everything in latitude longitude
> - EPSG 3857 : this makes everything in meters from the equator (I think)
> and we need to get the data in this format when we want to do things in
> physical distance terms like making a 1km distance buffer or measuring areas
>
> I haven't learned GIS stuff from theory, I just use it, so don't know more
> details about CRS. I do understand that the dizzying multitude of CRS's out
> there are so because apparently GIS folks like to re-orient the center of
> the world (geometrically speaking) to where their data is to ensure least
> distortion of their shapes in the rendering. When I come across anything
> that's in a non-standard CRS, my first move is to transform it to either
> lat-longs (4326) or meters (3857).
>
> Regards
> Nikhil VJ
>
>
> On Monday, April 15, 2019 at 1:57:20 PM UTC+5:30, Ashim wrote:
>>
>> Dear All,
>>
>> I am referring to 2011_Dist. * set of shapefile. (District level
>> shapefiles).
>>
>> When I read them as simple features in R, ( like this )
>>
>> map <- st_read("2011_Dist.shp") %>% st_as_sf()
>>
>> ( it's unprojected because it says 4326 in the epsg when I read the above
>> )
>>
>> plot(map$geometry)
>>
>> it looks OK.
>>
>> But when I do :
>>
>> map <- st_read("2011_Dist.shp") %>% st_as_sf() %>% st_transform(crs= 2154)
>>
>> plot(map$geometry)
>>
>> the map is TILTED.
>>
>> What is the correct projection to use for this dataset? Please clarify.
>>
>> Best Regards,
>> Ashim
>>
> --
> Datameet is a community of Data Science enthusiasts in India. Know more
> about us by visiting http://datameet.org
> ---
> You received this message because you are subscribed to the Google Groups
> "datameet" group.
> To unsubscribe from this group and stop receiving emails from it, send an
> email to datameet+unsubscr...@googlegroups.com.
> For more options, visit https://groups.google.com/d/optout.
>

-- 
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us by visiting http://datameet.org
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map.R
Description: Binary data

Re: [datameet] Re: Correct CRS for datameet maps

[Devdatta Tengshe]

HI Ashim, & others,

Coordinate systems, and their area of applicability is an abstruse topic,
and one that has many complicated things to consider. So what I'm saying
here is a user-friendly summary.


   - The data in our Repository is in WGS-84 Lat/long, which has the EPSG
   code 4326.
   - You seem to be projecting it to ESPG: 2154, which is coordinate system
   applicable in France.( http://epsg.io/2154)  I can't see a Valid reason
   for doing this.
   - If you need to project to a projected Coordinate System,(Maybe for
   calculating areas & distances) you should use EPSG:7755, (
   http://epsg.io/7755) which is the one defined in NNRMS standards, and is
   used by many Government Organizations, like ISRO, NURM etc.
   - I generally* won't recommend* projecting to EPSG:3857, which is the
   webmercator projection, since it has several issues. *You should never
   measure areas or distances using this projection*.




Regards,
Devdatta


On Tue, Apr 16, 2019 at 11:42 AM Nikhil VJ  wrote:

> Hi Ashim,
>
> Pls provide the exact link of what you're referring - this stuff is never
> as much on the top of people's minds as we assume it to be.
> Do try loading your shapefiles on other tools and check there :
> mapshaper.org is a site that does a lot of quick, cool things with
> shapefiles; QGIS is a software that does everything with shapefiles. Both
> are free and open source.
>
> The latter will help you re-save the shapefile into any CRS you want.
> Right-click the layer > Save As (or "Export") and remember to choose your
> preferred CRS in the dropdown.
>
> Can you give background on what this CRS : *2154* : is and why you want
> to transform to that? Because I've only come across two main CRS's both
> being under the "WSG 84" category :
> - EPSG 4326 : this makes everything in latitude longitude
> - EPSG 3857 : this makes everything in meters from the equator (I think)
> and we need to get the data in this format when we want to do things in
> physical distance terms like making a 1km distance buffer or measuring areas
>
> I haven't learned GIS stuff from theory, I just use it, so don't know more
> details about CRS. I do understand that the dizzying multitude of CRS's out
> there are so because apparently GIS folks like to re-orient the center of
> the world (geometrically speaking) to where their data is to ensure least
> distortion of their shapes in the rendering. When I come across anything
> that's in a non-standard CRS, my first move is to transform it to either
> lat-longs (4326) or meters (3857).
>
> Regards
> Nikhil VJ
>
>
> On Monday, April 15, 2019 at 1:57:20 PM UTC+5:30, Ashim wrote:
>>
>> Dear All,
>>
>> I am referring to 2011_Dist. * set of shapefile. (District level
>> shapefiles).
>>
>> When I read them as simple features in R, ( like this )
>>
>> map <- st_read("2011_Dist.shp") %>% st_as_sf()
>>
>> ( it's unprojected because it says 4326 in the epsg when I read the above
>> )
>>
>> plot(map$geometry)
>>
>> it looks OK.
>>
>> But when I do :
>>
>> map <- st_read("2011_Dist.shp") %>% st_as_sf() %>% st_transform(crs= 2154)
>>
>> plot(map$geometry)
>>
>> the map is TILTED.
>>
>> What is the correct projection to use for this dataset? Please clarify.
>>
>> Best Regards,
>> Ashim
>>
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[datameet] Re: Correct CRS for datameet maps

[Nikhil VJ]

Hi Ashim,

Pls provide the exact link of what you're referring - this stuff is never 
as much on the top of people's minds as we assume it to be.
Do try loading your shapefiles on other tools and check there : 
mapshaper.org is a site that does a lot of quick, cool things with 
shapefiles; QGIS is a software that does everything with shapefiles. Both 
are free and open source.

The latter will help you re-save the shapefile into any CRS you want. 
Right-click the layer > Save As (or "Export") and remember to choose your 
preferred CRS in the dropdown.

Can you give background on what this CRS : *2154* : is and why you want to 
transform to that? Because I've only come across two main CRS's both being 
under the "WSG 84" category : 
- EPSG 4326 : this makes everything in latitude longitude
- EPSG 3857 : this makes everything in meters from the equator (I think) 
and we need to get the data in this format when we want to do things in 
physical distance terms like making a 1km distance buffer or measuring areas

I haven't learned GIS stuff from theory, I just use it, so don't know more 
details about CRS. I do understand that the dizzying multitude of CRS's out 
there are so because apparently GIS folks like to re-orient the center of 
the world (geometrically speaking) to where their data is to ensure least 
distortion of their shapes in the rendering. When I come across anything 
that's in a non-standard CRS, my first move is to transform it to either 
lat-longs (4326) or meters (3857).

Regards
Nikhil VJ


On Monday, April 15, 2019 at 1:57:20 PM UTC+5:30, Ashim wrote:
>
> Dear All,
>
> I am referring to 2011_Dist. * set of shapefile. (District level 
> shapefiles).
>
> When I read them as simple features in R, ( like this ) 
>
> map <- st_read("2011_Dist.shp") %>% st_as_sf()
>
> ( it's unprojected because it says 4326 in the epsg when I read the above )
>
> plot(map$geometry)
>
> it looks OK.
>
> But when I do : 
>
> map <- st_read("2011_Dist.shp") %>% st_as_sf() %>% st_transform(crs= 2154)
>
> plot(map$geometry)
>
> the map is TILTED.
>
> What is the correct projection to use for this dataset? Please clarify.
>
> Best Regards,
> Ashim
>

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