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http://spatialtech-humanities.com/

11 Aug

I recently migrated all the content from this blog to my new website!

www.spatialtech-humanities.com, I’m looking forward to see you there.

Hi all,

I hope you are having a great summer! Just a quick note to say that I’m migrating my blog to my new website. I hope you like it and continue following my research. Don’t hesitate to contact me anytime šŸ™‚

Book: Thinking Beyond the Tool. Archaeological Computing and the Interpretive Process

15 Feb

Hey guys,

Just a quick note to let you know that our book Ā “Thinking Beyond the Tool: archaeological computing and the interpretive process” (cover by Javier Pereda) is already in press.

The idea of putting together this book was inspired by theĀ session ā€˜Thinking beyond the Tool: ArchaeologicalĀ Computing and the Interpretive Processā€™, which was heldĀ at the Theoretical Archaeology Group (TAG) conferenceĀ in Bristol (17-19 December 2010). The book postulates that archaeological computing has become an integral part of theĀ interpretive processĀ for inquiring and disseminating the past and includes:

  • 12 theoretically informed chapters on a variety of computational methodologies used in archaeology and heritage
  • an introduction by the editors (Costas Papadopoulos, Angeliki Chrysanthi and myself)
  • a commentary by Jeremy Huggett
The book will be out by the end of March and those of you coming to the CAA2012 keep an eye for it at theĀ ArchaeopressĀ stand! Many thanks to all those ā€“ both authors and reviewers-Ā who haveĀ contributed to this!

CAA2012 – Extended Deadline

1 Dec

CAA2012 – Extended Deadline

It has been a crazy day at CAA2012 HQ. We are now approaching 300 submissions for the conference, with an amazing range of topics. So, thank you VERY much for your submissions.

We have also received a lot of requests for slightly more time, and so we have decided to extend the deadline until 11:59pm UK time on Wednesday 7th December. Submission is via theĀ Open Conference System.

We will still endeavour to release the programme before Christmas so to help the referees please get your submissions in as early as possible.

We will also be announcing the registration fees and process next week.

The website also carries details of the StudentĀ BursaryĀ application process which is now open. Also remember theĀ Recycle Award.

Finally you can now follow us on twitter viaĀ #caasoton

Online tool to convert .kml to .shp

1 Aug

Hi guys, today I just wanted to share with you a very useful tool that I found.

Is called Kml2Shp and it exports online any kml to ESRI shapefile format or the other way around. Very nice tool šŸ™‚

http://www.zonums.com/online/kml2shp.php

How to extract the values from Time series data in Idrisi

15 Apr

Hello guys,

Time series data

With GIS you can explore a series of rasters depicting Ā the same geographical area through time,Ā analyzingĀ how an specific element or attribute changes. This is one of the purposes of Time series data. So, theĀ other day I exchange a series of interesting emails with Idham Khalil from the Geography Department here at uni about how to extract and compare the values from a series of images.

If you have only few images, one way to compare two rasters is toĀ subtract Ā one image from the other to see the changes through time, but of course it depends on the question you need to solve. On the other hand, if you have plenty images here is the solution to which Idham arrived using Idrisi Taiga:

Let say you are working with time series data and have hundreds of images(layers). And you want to find the behaviour of one pixel/polygon over times. One way of doing it is using earth Trend Modeler module in Idrisi Taiga. Load all the images in earth trend modeler and make them a raster group.Then go to Explore Temporal Profiles. This will generate a time series curve of certain pixel/region depending on your objective. Right click on the graph produced and …copy to clickboard as text(data only). Bingo….you will have the values of all those years.

As always, I deeply enjoy these conversations with other people so if you have something in mind that we can discuss regarding technical or theoretical issues behind GIS, please feel free to contact me šŸ™‚

Happy modelling!

GIS and Google Earth

24 Feb

Hello again guys!

Today somebody asked me about getting GIS data into google earth.

This software has the great advantage that you can see loads of different data that you don’t necessary have in your regular GIS, such as picturesĀ of a site that is of your interestĀ uploadedĀ by the community , tracks, wikiinfo and so on. So there are good reasons for you to want your gis regular data displayed here. The problem that my friend had was that when he “imported” his data into google he realized that it was a little bit “off” place.

Ok. This is basically due because the coordinate system he used was the one he had originally set for his data.Ā KML only supports WGS84, so in order for you to display your data correctly you need to “reproject” your data to to WGS84. In arcgis (as in other software) this is really easy.

Happy modelling šŸ™‚

Free GIS and Spatial Data Analysis Software

23 Feb

Hey guys,

Just a quick post to tell you about this great software I found recently.

MapWindow seems to have great potential to get layers into a diversity of formats, while GeoDa offers all these facilities:

  • Data Input and Output
    • read and write shape files
    • copy graphs and maps to clipboard
    • save maps and graphs to bitmap file
  • Spatial Data Manipulation
    • create point shape files from text files
    • centroids for polygons
    • Thiessen polygons from points
    • contiguity based spatial weigths for polygons
    • distance based spatial weights for points and polygons
  • Visualization and Queries
    • graphs, maps and table
    • linking and brushing of all maps and graphs, multiway linking of table
    • spatial selection on maps
    • query selection in table
  • Mapping
    • quantile and standard deviational maps
    • outlier maps: box map and percentile map
    • rate mapping and smoothing: excess risk map, Empirical Bayes smoothing, spatial smoothing
    • map movie
  • EDA
    • histogram
    • box plot
    • scatter plot
    • full dynamic linking and brushing
  • Spatial Statistics
    • Moran’s I
    • Moran scatterplot: univariate, bivariate, EB corrected
    • LISA local Moran: univariate, bivariate, EB corrected

    I hope is of some use to you! šŸ™‚

    Recursos de SIG y Geomatica para Latinoamerica (GIS & Geomatics for Latin America)

    21 Feb

    Hola!
    Esta vez les escribo para compartirles un excelente sitio de recursos de Geomatica y SIG Libre que puede ser especialmente util para quienes trabajan en Mexico y otras partes de America.Ā Espero que hayan tenido un buen fin de semana y pronto les platicare sobre cuestiones tecnicas respecto a la combinacion de analisis de visibilidad y movimiento šŸ˜€

    Workaround for Arcgis batch models (or what to do when batching a model just fails)

    14 Feb

    Ok, so many of you are probably already aware that when you create a model in Arcgis in order to batch it you need to make the variables lists. However, there are sometimes that this just fails and it not allows you to batch your model. I encountered this problem working with a quite complicated model and looking for different solutions I figured out this one.Ā You can justĀ create a script instead of a model, but if you don’t have time or you are not a super scripting nerd šŸ˜€ there is another way to make it work. Is actually quite similar to the way you do macros in IDRISI.

    For the sake of explanation here Im going to put as example a simple process (create a buffer):

    Let’s say you create your model and you want to batch process it.

    1.Open the command line either in Arcmap or Arccatalog. To make sure that your model works well before you create your workflow in Excel, enter the parameters of your model in the command line and run it.

    2. Once you are sure it is working properly, copy the parameters to a worksheet in excel.

    (If you are using arccatalog you can set the absolute paths to your layers, but if you added all the information into an arcmap project the model will take the relative paths so in the parameters you can just input the name of the file rather than the whole path)

    3. Once in excel you can just drag down the values filling up the parameters,Ā modifyingĀ the names of the files you want to run in subsequent models.

    4. Delete all the other sheets in the book (Sheet1,2 and so on TAB/right click/delete). Save as .cvs (Comma delimited).

    (This will allow you to modify in the next step the file and save it directly to .txt)

    5. Open it your word processor, click Find and Replace. Replace “,” for one space.

    6. Save the document as .TXT

    7. Open it in Notepad.

    8. Copy and paste all in the command line and run it! (you are ready to go for a nice coffee while the machine works for you :D)

    You can do the same with more complex models, just add the parameters that are necessary in your model.

    Have a great day!

    How to batch merge multiple shapefiles

    11 Feb

    Hey guys, in one of my last posts I shared a very useful tool to split a shp into several by attribute. Ā I found another great script by Gerry GabrischĀ but this time to merge multiple shapefiles. There are several ways to do this and if you are not that familiar establishing the arguments or parameters in a Phyton script you will probably prefer this other utility.

    Tlaloc bless the internet! šŸ˜€

    Have a great weekend!

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