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11 Aug

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

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 ¬†“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 the¬†session ‚ÄėThinking beyond the Tool: Archaeological¬†Computing and the Interpretive Process‚Äô, which was held¬†at the Theoretical Archaeology Group (TAG) conference¬†in Bristol (17-19 December 2010). The book postulates that archaeological computing has become an integral part of the¬†interpretive process¬†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 the¬†Archaeopress¬†stand! Many thanks to all those ‚Äď both authors and reviewers-¬†who have¬†contributed to this!

Second Call for Papers Computer Applications in Archaeology 2012

26 Nov

CAA Southampton

CAA2012 Call for Papers

Submissions are requested for the 2012 Computer Applications and Quantitative Methods in Archaeology to be hosted by the Archaeological Computing Research Group in the Faculty of Humanities at the University of Southampton.

The main aim of the CAA conference is to bring together researchers, professionals and students with an interest in the field of computer applications and quantitative methods in archaeology. We therefore welcome submission of abstracts in English of up to 500 words that:

–¬†¬†¬†¬†¬†¬†¬†¬†¬†¬†¬†¬†¬† Describe original, technically excellent, critical, and/or synthetic research

–¬†¬†¬†¬†¬†¬†¬†¬†¬†¬†¬†¬†¬† Focus on interesting computation and/ or quantitative methods and theories applied in archaeology and related disciplines

You may choose to present your research via a long paper (20 minutes plus 10 minutes for questions and handover), short paper (10 minutes plus 5 minutes for questions and handover), or a poster. You may submit your research to a specific proposed session or to the general session. Poster sessions will run on each day of the conference and posters will be linked in the conference documents and website to the sessions to which they were submitted. Please indicate your preference in your submission.

Provisionally the conference will be divided into six themes:

1.            Data Analysis, Modelling, Management, Integration and Visualisation

2.            Field and Lab Recording

3.            Geospatial technologies

4.            Human Computer Interaction, Multimedia and Museums

5.            Simulating the Past

6.            Theoretical Approaches and Context of Archaeological Computation

The list of proposed sessions is available online:

You should submit your paper via the CAA2012 Open Conference System available online:

The deadline is 11:59pm 30 November 2011. Accepted papers will be announced and conference booking system will open on 21st December 2011. Please note that at least one of the authors of a paper or poster must be registered for and attend the conference.

All research presented at CAA2012 may be submitted after the conference for peer review for publication in the conference proceedings. These will be published prior to CAA2013.

Note: If you would like your paper to be considered for the CAA Recycle Award then please indicate this in your submission:

Look also for our session about the study of movement:

Loc(i) Motion: Current technologies and computational methodologies for exploring human movement in the past and present

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 ūüôā

Script to sum values from one field and place them into another field ARCGIS

31 May

Hi guys,

Today I had to sum the values from a field from a raster file and write the output into another. Despite you’ll think that Arcgis would have a tool to do this in a simple way, I found out that this was not necessarily the case :p

I wrote an script in python to solve this. I hope you find it useful.

What the script does is to sum the values from a field writing the result into another field in the table.

You can copy this and add it into your toolbox ūüôā

The arguments that are necessary are:

#(1) table = table containing the field you want to sum

#(2) fieldtosum= the field that you are going to sum

#(3) fieldwrite= the field in which the sum is going to be writen

import arcgisscripting, sys
gp = arcgisscripting.create()
table = sys.argv[1]
fieldtosum = sys.argv[2]
fieldwrite = sys.argv[3]

rows = gp.SearchCursor(table)
row = rows.Next()
p = 0.0
while row:
p += row.getvalue(fieldtosum)
print p
row =
#calculate field

Very soon I’ll be writing about how to do a series of variants of visibility analysis such as “Directional Viewsheds” and “Higuchi Viewsheds” that can be very useful in archaeology ūüôā

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  the same geographical area through time, analyzing how an specific element or attribute changes. This is one of the purposes of Time series data. So, the 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 to subtract  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 ūüôā

Happy modelling!

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! ūüôā

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