From Wikipedia: In computing, floating point describes a method of representing an approximation to real numbers in a way that can support a wide range of values. The numbers are, in general, represented approximately to a fixed number of significant digits (the mantissa) and scaled using an ...

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2
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1answer
29 views

arcpy cursor not accepting float(Inf)

I have a vector layer in which I have added some fields of type 'float' using arcpy.AddField_management. I'm performing simple calculations between those fields using update cursors but the problem is ...
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1answer
32 views

How to round up/down an pixel value of a raster to a pixel value with 2 decimal places?

I have a raster (DTM) with floating points as pixel value. Now i want to round up/down the pixel values (to its next nearest value) to 2 decimal places. I use ArcGIS (with extensions) and tried the ...
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0answers
10 views

Conversion of Polygon vector files to Raster GRID 8 bit unsigned integer

I am trying to convert a polygon shapefile layer into Raster GRID with 8 bits and which is unsigned integer. I managed to convert the shapefile in ArcGIS with the Arc Toolbox Conversion tools, but the ...
0
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0answers
26 views

Simple query not returning values

I have a super simple select by attribute query "Coefficient" = #, the #'s are 0, .2, .3, etc... to 1. The query will select some of the #s but not others. Example) when I query 0,1,.5 the attributes ...
1
vote
1answer
39 views

How to reclass aspect raster to float values

So I have an aspect raster that was created from a DEM. I'm trying to reclassify it using python, but I'm running into some issues. Here's the setup: I need to reclassify values in the aspect raster ...
0
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1answer
33 views

How to interpolate integer rasters to floating point?

I have an reclassified raster, I need to convert it to floating point, the "float" tool does not suffice, because I need the output values to be spatially interpolated. For example, at the midpoint of ...
1
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0answers
83 views

Why does GeoServer's GetFeature round my numbers, but only for outputFormat=CSV?

When I make a GetFeature request with outputFormat=CSV to my GeoServer v2.4.5 I'm finding that the floating point numbers in my returned data have been rounded. When I make the same request with ...
1
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1answer
417 views

Raster Multiplication - Can't Multiply Sequence by Non-Int of Type “Float”

I am trying to multiply a list of GRID raster datasets using a different value for each raster. The value is in the raster name. Some examples are [wse_1979_5,wse_1980_0,wse_1980_5], where 1979_5, ...
1
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1answer
250 views

Floating point calculations in QGIS

How do I manage floating point calculations in QGIS? I have carried out 3 consecutive calculations on landsat bands. I end up with 32 bit floating point rasters on which I can't carry out a 4th ...
3
votes
3answers
2k views

How can I reclassify a raster to floating point values?

I have a raster of landuse values that I need to reclassify into pollution concentration values. I have the pollution values in a separate table. They are decimal values (ex. 0.0056), and my landuse ...
6
votes
1answer
495 views

How can I snap lines in PostGIS?

I have a few linestrings that together form a long line. The start- and endpoints of the linestrings are equal with their direct neighbour, but when tested the ST_Distance between any 2 lines is like ...
8
votes
2answers
4k views

How to fully load a raster into a numpy array?

I have been trying to check my filters on DEM raster for pattern recognition and it is always resulting in missing last rows and columns(like..20). I have tried with PIL library, image load. Then with ...
2
votes
4answers
462 views

Floating point: understanding their inaccuracy [closed]

I am trying to understand why a floating point is inaccurate. Please bear in mind that I am not a mathematician. What is exactly the difference between floating point and double integers? and why use ...
19
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2answers
427 views

Precision when working with spatial data in GIS

Is there a basic or introductory study that examines and compares the precision of spatial data when working with varying precison of the data input, like having 1, 2, ... decimal places? with the ...
8
votes
1answer
764 views

In ESRI ArcMap, how do I refer to NaN or ±∞ (special floating point values) in definition queries?

I have by chance discovered how ESRI ArcMap displays special floating point values to the user. +∞ (positive infinity) is displayed as 1.#INF –∞ (negative infinity) would supposedly be displayed as ...