[RS-ecology] Problems with change vector analysis

[Johannes Joscha Vogel]

Dear remote sensing community,


I am currently working on droughts and heat waves in the Mediterranean and I would like to apply a change vector analysis to display how the variables changed over time. So, instead of spectral layers (which seems the usual case for a change vector analysis), I am using different variables here.
Unfortunately, using the command rasterCVA it does work, even though I tried to do it like in the example of the help page.
Any help on this issue would be really appreciated. I attached the code and the corresponding workspace

Best regards,
Johannes Vogel

-- 
Johannes Joscha Vogel

Research Assistant (MSc)
DFG Research Training Group 'NatRiskChange'

University of Potsdam
Institute of Environmental Science and Geography
Karl-Liebknecht-Str. 24-25
14476 Potsdam-Golm

Phone: +49 331 977 6257
E-mail: joschavogel at uni-potsdam.de

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library(raster)
library(RStoolbox)

load('Workspace_change_vector_analysis.RData')
# Workspace contains these 3 rasterbricks:
# brick_1stperiod_h_d # Heat waves and droughts in the first time span
# brick_2ndperiod_h_d # Heat waves and droughts in the second time span
# brick_bothperiods_h_d # Heat waves and droughts in both time spans (contains the information of the two bricks above)


rasterCVA(brick_1stperiod_h_d,brick_2ndperiod_h_d)
rasterCVA(brick_bothperiods_h_d[1:2],brick_bothperiods_h_d[3:4])

# both ways it does not work


# For comparison:
# Example code from help section (data structure organized in the same way)

## Create example data
data(lsat)
pca <- rasterPCA(lsat)$map

## Do change vector analysis 
cva <- rasterCVA(pca[[1:2]], pca[[3:4]])
cva
plot(cva)


# Comparison of file structure does not show any apparent differences
View(pca)
View(brick_bothperiods_h_d)
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