# Tagged Questions

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 ...

483 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 ...
11k 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 ...
1k views

### Referring to NaN or ±∞ (special floating point values) in ArcMap definition queries?

I have by chance discovered how ArcMap displays special floating point values to the user. +∞ (positive infinity) is displayed as 1.#INF –∞ (negative infinity) would supposedly be displayed as -1.#...
924 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 ...
608 views

### How can I get ArcMap 10.2 to recognize a csv column as float and not int?

I am trying to show a .csv file (2 columns, 291 rows) in ArcMap 10.2 using Catalog window to drag the .csv file into ArcMap. The second column of the .csv is a floating point number (range is [0-1]), ...
5k 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 ...
679 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 ...
220 views

### Creating flt (floating point raster) with QGIS

I would like to create a flt (floating point raster) with QGIS to use later as a terrain in Hec RAS RAS-Mapper. With Raster -> Conversion -> Translate there is no option to create a flt. Is there ...
63 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 ...
75 views

### arcpy handling of floating points

This arises from my own question How to handle coordinates accuracy in ArcGIS where I have tried to use the documentation entitled Using geometry objects with geoprocessing tools as a reference. I ...
1k 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, ...
99 views

### Is it possible to round all coordinates in shapely?

Following on from How can I add points to a LineString in shapely?, I'm hitting a problem where floating point representations mean objects aren't precisely where I expect them be after they are moved ...
26 views

### Any open source raster applications that accept floating point rasters with attribute tables?

I understand that Arc floating point rasters don't have attribute tables because of the high potential number of unique values in each cell but at a theoretical level, I think a floating point raster ...
200 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 ...
745 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 ...
26 views

### gdal_polygonize floating values [duplicate]

gdal_polygonize converts whatever rasters values into vector integers as it is based on the GDALPolygonize() function (http://gdal.org/gdal__alg_8h.html#a3f522a9035d3512b5d414fb4752671b1). It is ...
221 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 ...
185 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 ...
1k 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 ...