4
votes
Accepted
Maxent error 'java.lang.NumberFormatException: For input string:"Z^,,,"'
This error is caused because your raster is actually GeoTIFF file with .asc extension, which is unsupported by MaxEnt.
You can check this in raster metadata (or by running gdalinfo from comamnd line, ...
- 6,935
4
votes
Difference between Bootstrap and Cross Validation MaxEnt
Cross validation splits your training data into a number of groups. Maxent then calibrates a model on a number of those groups and tests it on the the groups left out (say 2/3rd's of the folds as ...
- 2,176
4
votes
Accepted
Creating Raster Map including if condition in QGIS
With the Raster Calculator under QGIS > Raster menu:
(current@1 = 0 AND 2050@1 = 0) * 0 +
(current@1 = 1 AND 2050@1 = 1) * 1 +
(current@1 = 2 AND 2050@1 = 2) * 2 +
(current@1 = 3 AND 2050@1 = 3) * ...
- 15.9k
3
votes
Correlation analysis between large number of environmental rasters
If you have enough memory to read in and correlate two rasters you can do it one pair at a time.
I've created a sample set of four .asc raster files.
> rastlist
[1] "r1.asc" "r2.asc&...
- 65.6k
3
votes
Accepted
How maxent's algorithm uses data to predicte distribution of species
You can say it's a model or an estimate of that species might be distributed in 2070, but you don't know for certain that is where this species will be in 2070. The bioclimatic variables for 2070 are ...
- 2,417
3
votes
Accepted
No Data was found error after applying a MaxEnt classifier (GEE)
This error message, Error Message: classification: Layer error: No data was found in classifier training input. usually means what it says. If you print sampleData, you'll see it's an empty feature ...
- 14.5k
2
votes
Fixing raster.asc to work with Maxent?
To run MaxEnt all environmental data must have the exactly same extent, cell size and coordinate system.
You can achieve this several ways (QGIS, GDAL, R, ...) look at Changing pixel size in 'asc' ...
- 6,935
2
votes
dismo - Plotting individual predictor responses
Not sure whether this is what you are looking for, but: if you use response() specifying a single variable, the function will plot and invisibly return the x, y, data. Is that what you are looking for?...
- 2,031
2
votes
Extracting raster values from polygon perimeters using ArcGIS Spatial Analyst?
If you are wanting to extract the pixel values for a polygon boundary rather than the interior area, then you need to convert your polygons into polylines. You don't actually state what GIS system you ...
- 44.2k
2
votes
Can I consider as continuous data vegetation layers on Maxent?
I do not know where you picked up the idea that it is "advised to condenser vegetation categorical" but, this is not empirically justified. For nonparametric models, I always tell my students to ...
- 32k
2
votes
Connecting presence point to nearest raster (brick)
Strategy: convert the raster to a set of x,y,value points at the non-NA locations and use a fast nearest neighbour match to get the nearest raster cell value.
Example data: a 10x10 raster of values ...
- 65.6k
2
votes
Accepted
Differences in MaxEnt between 'Biomod2' and 'Dismo' package
The issue here is that you are not using pseudo absences (but only true absences). This setting is not obtimal at all for MAXENT that is optimize design to spot te difference between presences and the ...
1
vote
Accepted
Area calculation of classified raster layer
You have to use a CRS that
1 is a projected (ot geographic) CRS, thus units not in degrees, but in meters (or any other length unit) and
2 does not distaort area. So you need an equal area CRS. ...
- 73.8k
1
vote
Accepted
How to process environmental data for the input in MaxEnt (or any other modelling platform)
Taken from A Brief Tutorial on Maxent:
The directory “layers” contains a number of ascii raster grids (in
ESRI’s .asc format), each of which describes an environmental
variable. The grids must all ...
- 6,018
1
vote
Error saving .asc bias file in R
Its always a good idea to set up a simple small example you can check visually what's going on. Let's make a 10x10 pixel matrix:
library(MASS)
library(raster)
r = raster(matrix(1:100,10,10))
r[] = 0
...
- 65.6k
1
vote
Accepted
Maxent can't get past "javalang.ClassCastExeption: [D cannot be cast to [F" error message
Try updating your Java version or, using a older maxent version
1
vote
Error when executing maxent algorithm with categorical variable
I had the same problem, but specifying the categorical variable by its index number (in the stack), not by its name, did the trick.
- 11
1
vote
Getting startAsciiWriting (x, filename, ....) error in R?
I imagine that your code is going sideways in the projectRaster function. You do not have the res argument defined so, it is likely that the cell resolution is not the same in the x,y dimensions. ...
- 32k
1
vote
Extracting residuals of maxent model in R?
Only half an answer: maxent() returns an object of the class MaxEnt. The fact that this is an S4-type object doesn't matter much here, but if you want top know more about that you can read on here. ...
- 268
1
vote
Accepted
Converting .tif to .asc for MaxEnt
The data in your original TIFF is stored as "Float64 - Sixty four bit floating point". This is a standard binary format for decimal numbers. The standard includes special binary numbers for encoding ...
- 65.6k
1
vote
Running MaxEnt modelling in "dismo" using "loop" and storing the results in seperate objects and folders
I worked on the problem through the day and came up with the following solution. I hope it will come handy for everyone.
# Creating the objects
x <- stack()
threshold.m <- vector("...
- 31
1
vote
Accepted
How can I calculate averaged response curves for Maxent models fitted using maxnet package in R?
Here's a couple of function that get you 90% of the way. Its hacked out of response.plot:
#' get the responses for variable v in a list of models
#' use min and max for the range of the variable, ...
- 65.6k
1
vote
Translating tif rasters to asc taking a long time
As a test to see whether it is faster you can run gdal_translate from the OSGeo4W shell using the instructions here: http://www.gdal.org/gdal_translate.html
Essentially navigate to your directory ...
- 3,948
1
vote
Accepted
Translating tif rasters to asc taking a long time
I have been using the translate tool and sometimes, I don't know why, is too slow. You have two options:
If you can have access to a pc with arcgis, try the tool "from raster to ascii" (ArcToolbox/...
- 3,494
1
vote
WorldClim Variables to Maxent?
First, I would recommend to download the data (the 19 bioclim variables I suppose) in a more accessible format (in terms of ease using common software / packages). GeoTiff should be fine. You can get ...
1
vote
Creating contiguous dispersal surface between two climate-change scenarios in ArcGIS for Desktop?
If you have access to the ArcGIS Spatial Analyst extension, I would use the Region Group tool, then filter on value and count using the Con or SetNull and Lookup tools.
You could chain them together ...
- 67.8k
1
vote
MAXENT and shapefiles?
General summary:
You have to create raster from your vector layer (rasterizing) which must have the exactly same extent, cell size and coordinate system as your other environmental data. Than set ...
- 6,935
1
vote
Kriging predictions for presence only data with Maxent
Interesting method to use; have you considered running the model with equal numbers of pseudo absences and then increasing or decreasing the proportion of known absences to pseudo absences to see if a ...
- 2,176
1
vote
r.maxent.lambdas command not recognized in GRASS after installing extension
The installation fails on Windows because r.maxent.lambdas is a shell script and not a Python script. The options are
rewrite it using Python (perhaps contact the author?)
use a non-Windows operating ...
- 13k
1
vote
Making Raster of Northings (for use in Maxent) in ArcMap?
I created a polyline feature along southern extent of my raster layer, and then used the Euclidean Distance tool to create a raster of distances from that polyline. I'm going to use "distance from ...
- 41
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