MAPS="map_1 map_2 map_3 map_4 map_5 map_6 map_7"
maxn=10

for map in ${MAPS} ; do
    r.mapcalc --o expr="${map} = rand(0,$maxn)" 
    echo ${map} >> map_list.txt 
    maxn=`expr $maxn + 10`
done

t.create type=strds temporaltype=absolute \
         output=precipitation_daily \
         title="Daily precipitation" \
         description="Test dataset with daily precipitation"

t.register -i type=rast input=precipitation_daily \
           file=map_list.txt start="2012-08-20" increment="1 days"

t.info type=strds input=precipitation_daily
 +-------------------- Space Time Raster Dataset -----------------------------+
 |                                                                            |
 +-------------------- Basic information -------------------------------------+
 | Id: ........................ precipitation_daily@ecad90_sample_tmodules
 | Name: ...................... precipitation_daily
 | Mapset: .................... ecad90_sample_tmodules
 | Creator: ................... lucadelu
 | Creation time: ............. 2013-11-08 10:38:18.782948
 | Temporal type: ............. absolute
 | Semantic type:.............. mean
 +-------------------- Absolute time -----------------------------------------+
 | Start time:................. 2012-08-27 00:00:00
 | End time:................... 2012-09-03 00:00:00
 | Granularity:................ 1 day
 | Temporal type of maps:...... interval
 +-------------------- Spatial extent ----------------------------------------+
 | North:...................... 75.5
 | South:...................... 25.25
 | East:.. .................... 75.5
 | West:....................... -40.5
 | Top:........................ 0.0
 | Bottom:..................... 0.0
 +-------------------- Metadata information ----------------------------------+
 | Raster register table:...... precipitation_daily_ecad90_sample_tmodules_raster_register
 | North-South resolution min:. 0.25
 | North-South resolution max:. 0.25
 | East-west resolution min:... 0.25
 | East-west resolution max:... 0.25
 | Minimum value min:.......... 0.0
 | Minimum value max:.......... 0.0
 | Maximum value min:.......... 9.0
 | Maximum value max:.......... 69.0
 | Number of registered maps:.. 7
 |
 | Title:
 | Daily precipitation
 | Description:
 | Test dataset with daily precipitation
 | Command history:
 | # 2013-11-08 10:38:18 
 | t.create type="strds" temporaltype="absolute"
 |     output="precipitation_daily" title="Daily precipitation"
 |     description="Test dataset with daily precipitation"
 | # 2013-11-08 10:38:26 
 | t.register -i type="rast" input="precipitation_daily"
 |     file="map_list.txt" start="2012-08-20" increment="1 days"
 |
 +----------------------------------------------------------------------------+

 
t.rast.univar -eh precipitation_daily
id|start|end|mean|min|max|mean_of_abs|stddev|variance|coeff_var|sum|null_cells|cells|first_quartile|median|third_quartile|percentile_90
map_1@ecad90_sample_tmodules|2012-08-27 00:00:00|2012-08-28 00:00:00|4.50559701492537|0|9|4.50559701492537|2.87457821791815|8.2631999309295|63.8001625177694|420210|0|93264|2|5|7|9
map_2@ecad90_sample_tmodules|2012-08-28 00:00:00|2012-08-29 00:00:00|9.48865585863784|0|19|9.48865585863784|5.7779859624471|33.3851217822358|60.8936191651129|884950|0|93264|4|9|15|18
map_3@ecad90_sample_tmodules|2012-08-29 00:00:00|2012-08-30 00:00:00|14.47868416538|0|29|14.47868416538|8.63325210721546|74.5330419467402|59.6273253052818|1350340|0|93264|7|14|22|26
map_4@ecad90_sample_tmodules|2012-08-30 00:00:00|2012-08-31 00:00:00|19.4582046663236|0|39|19.4582046663236|11.5783111835479|134.05728986307|59.5034916226703|1814750|0|93264|9|19|29|36
map_5@ecad90_sample_tmodules|2012-08-31 00:00:00|2012-09-01 00:00:00|24.4868330759993|0|49|24.4868330759993|14.3850752287166|206.930389335835|58.7461644552805|2283740|0|93264|12|24|37|44
map_6@ecad90_sample_tmodules|2012-09-01 00:00:00|2012-09-02 00:00:00|29.4854391833934|0|59|29.4854391833934|17.2796032004376|298.584686764572|58.6038522029873|2749930|0|93264|15|30|44|53
map_7@ecad90_sample_tmodules|2012-09-02 00:00:00|2012-09-03 00:00:00|34.4274318064848|0|69|34.4274318064848|20.2238928524934|409.005842109134|58.7435419701681|3210840|0|93264|17|34|52|63