NAME¶

r.series - Makes each output cell value a function of the values assigned to the corresponding cells in the input raster map layers.

KEYWORDS¶

raster, series

SYNOPSIS¶

r.series r.series help r.series [-qn] input=name[,name,...] output= name[,name,...] method=string[,string,...] [ quantile=float[, float,...]] [threshold=float[, float,...]] [range=lo,hi] [-- overwrite] [--verbose] [--quiet]

Flags:¶

-q

 

Run quietly

-n

 

Propagate NULLs

--overwrite

 

Allow output files to overwrite existing files

--verbose

 

Verbose module output

--quiet

 

Quiet module output

Parameters:¶

input=name[,name,...]

 

Name of input raster map(s)

output=name[,name,...]

 

Name for output raster map

method=string[,string,...]

 

Aggregate operation

 

Options: average,count,median,mode,minimum,min_raster,maximum,max_raster,stddev,range,sum,threshold,variance,diversity,slope,offset,detcoeff,quart1,quart3,perc90,quantile,skewness,kurtosis

quantile=float[,float,...]

 

Quantile to calculate for method=quantile

 

Options: 0.0-1.0

threshold=float[,float,...]

 

Threshold to calculate for method=threshold

range=lo,hi

 

Ignore values outside this range

DESCRIPTION¶

r.series makes each output cell value a function of the values assigned to the corresponding cells in the input raster map layers. Following methods are available: average: average value count: count of non-NULL cells median: median value mode: most frequently occuring value minimum: lowest value maximum: highest value range: range of values (max - min) stddev: standard deviation sum: sum of values variance: statistical variance diversity: number of different values slope: linear regression slope offset: linear regression offset detcoeff: linear regression coefficient of determination min_raster: raster map number with the minimum time-series value max_raster: raster map number with the maximum time-series value

NOTES¶

With -n flag, any cell for which any of the corresponding input cells are NULL is automatically set to NULL (NULL propagation). The aggregate function is not called, so all methods behave this way with respect to the -n flag. Without -n flag, the complete list of inputs for each cell (including NULLs) is passed to the aggregate function. Individual aggregates can handle data as they choose. Mostly, they just compute the aggregate over the non-NULL values, producing a NULL result only if all inputs are NULL. The min_raster and max_raster methods generate a map with the number of the raster map that holds the minimum/maximum value of the time-series. The numbering starts at 0 up to n for the first and the last raster listed in input=, respectively. If the range= option is given, any values which fall outside that range will be treated as if they were NULL. The range parameter can be set to low,high thresholds: values outside of this range are treated as NULL (i.e., they will be ignored by most aggregates, or will cause the result to be NULL if -n is given). The low,high thresholds are floating point, so use -inf or inf for a single threshold (e.g., range=0,inf to ignore negative values, or range=-inf,-200.4 to ignore values above -200.4). Linear regression (slope, offset, coefficient of determination) assumes equal time intervals. If the data have irregular time intervals, NULL raster maps can be inserted into time series to make time intervals equal (see example). Number of raster maps to be processed is given by the limit of the operating system. For example, both the hard and soft limits are typically 1024. The soft limit can be changed with e.g. ulimit -n 1500 (UNIX-based operating systems) but not higher than the hard limit. If it is too low, you can as superuser add an entry in /etc/security/limits.conf # <domain> <type> <item> <value> your_username hard nofile 1500 This would raise the hard limit to 1500 file. Be warned that more files open need more RAM.

EXAMPLES¶

Using r.series with wildcards: r.series input="`g.mlist pattern='insitu_data.*' sep=,`" \
output=insitu_data.stddev method=stddev Note the g.mlist script also supports regular expressions for selecting map names. Using r.series with NULL raster maps: r.mapcalc "dummy = null()" r.series in=map2001,map2002,dummy,dummy,map2005,map2006,dummy,map2008 \
out=res_slope,res_offset,res_coeff meth=slope,offset,detcoeff Example for multiple aggregates to be computed in one run (3 resulting aggregates from two input maps): r.series in=one,two out=result_avg,res_slope,result_count meth=sum,slope,count Example for counting the number of days above a certain temperature using daily average maps ('???' as DOY wildcard): r.series input=`g.mlist rast pat="temp_2003_???_avg" sep=,` \
output=temp_2003_days_over_25deg range=25.0,100.0 method=count

SEE ALSO¶

g.mlist, g.region

AUTHOR¶

Glynn Clements Last changed: $Date: 2012-03-02 14:54:55 +0100 (Fri, 02 Mar 2012) $ Full index © 2003-2014 GRASS Development Team