Re: Interrogating lists of unequal lenghths

*To*: mathgroup at smc.vnet.net*Subject*: [mg67428] Re: Interrogating lists of unequal lenghths*From*: "kevin_jazz" <kevinbowman at mac.com>*Date*: Fri, 23 Jun 2006 04:31:55 -0400 (EDT)*References*: <e7aou4$92n$1@smc.vnet.net>*Sender*: owner-wri-mathgroup at wolfram.com

Thanks to everyone for the submission. I think simply mapping dimensions works. I'm still new at this so even the obvious solutions aren't evident until demonstrated. For my actual problem Dimensions /@ aura3399com {{70}, {125, 67}, {125, 67}, {125}, {125, 67, 67}, {125, 67}, {125}, {125, 25}, {125, 25}, {125}, {125}, {125}, {125, 67}, { 125}, {125}, {125}, {125, 67}, {125}, {125}, {125}, {125, 67, 67}, {125}, {125, 67}, { 125, 67}, {125, 67, 67}, { 125, 67}, {125}, {125}, {125}, {125}, {125}, {125}, {125}, {125}, {125}, { 125}, {125}, {125}, {125}, {125}, {125}, { 125}, {125}, {125}, {125}, {125, 67}, {125, 67, 67}, {125, 67}, {125}, {125}, {125}, {125}, {125}, {125}, { 125}, {125}, {125}, { 125}, {125}, {125}, {125}, {125}, {125}, {125}, {125}, {125}, {125}, \ {125}, {125}} I'm working on building a structure for HDF5 data, specifically for the NASA Aura spaceplatform, so I just figured out how to do this: TableForm[Transpose[{aura3399com[[1]], Map[Dimensions, aura3399com][[Table[ i, {i, 2, Length[aura3399com]}]]]}], TableAlignments -> {Left, Top}] Out[60]//TableForm= AirDensity 125 67 Altitude 125 67 AverageCloudEffOpticalDepth 125 AveragingKernel 125 67 67 AveragingKernelDiagonal 125 67 Calibration_QA 125 CloudEffectiveOpticalDepth 125 25 CloudEffectiveOpticalDepthError 125 25 CloudTopPressure 125 CloudTopPressureError 125 CloudVariability_QA 125 ConstraintVector 125 67 DegreesOfFreedomForSignal 125 DeviationVsRetrievalCovariance 125 InformationContent 125 Initial 125 67 KDotDL_QA 125 LDotDL_QA 125 MaxNumIterations 125 MeasurementErrorCovariance 125 67 67 NumberIterPerformed 125 O3 125 67 O3Precision 125 67 ObservationErrorCovariance 125 67 67 Pressure 125 67 RadianceResidualMax 125 RadianceResidualMean 125 RadianceResidualRMS 125 Scan_Averaged_Count 125 SpeciesRetrievalConverged 125 SpeciesRetrievalQuality 125 SurfaceEmissMean_QA 125 SurfaceTempConstraint 125 SurfaceTempDegreesOfFreedom 125 SurfaceTempError 125 SurfaceTempInitial 125 SurfaceTempObservationError 125 SurfaceTempPrecision 125 SurfaceTempVsApriori_QA 125 SurfaceTempVsAtmTemp_QA 125 SurfaceTemperature 125 TotalColumnDensity 125 TotalColumnDensityError 125 TotalColumnDensityInitial 125 TotalError 125 67 TotalErrorCovariance 125 67 67 VerticalResolution 125 67 BoresightAzimuth 125 BoresightNadirAngle 125 BoresightNadirAngleUnc 125 DayNightFlag 125 DominantSurfaceType 125 Latitude 125 Latitude_Footprint_1 125 Latitude_Footprint_2 125 Latitude_Footprint_3 125 Latitude_Footprint_4 125 LocalSolarTime 125 Longitude 125 Longitude_Footprint_1 125 Longitude_Footprint_2 125 Longitude_Footprint_3 125 Longitude_Footprint_4 125 Scan 125 Sequence 125 SolarZenithAngle 125 SurfaceElevStandardDeviation 125 SurfaceTypeFootprint 125 Tgt_SpacecraftAzimuth 125 Tgt_SpacecraftZenith 125 So, this allows me to figure out what elements are matrices or vectors. I think the depth will be good when the lists contain other objects as well. It would also be good to tell if the data is a string or a number. Many thanks, Kevin Bill Rowe wrote: > On 6/20/06 at 2:15 AM, kevinbowman at mac.com (kevin_jazz) wrote: > > >I'm trying to understand how to assess the dimensions of a list > >containing elements of unequal length. Let's say I have the list > > >U If, on the other hand, I set up the following list > > >In[5]:= x={{1},{2,3},{4,5,6,7}} > > >In[6]:= Dimensions[x] > > >Out[6]= {3} > > >The Dimensions command tells me I have only 3 elements. But, I need > >some way to figure out that the first sublist has length 1, second > >has length 2, and the third has length 4 in some automated fashion. > >I've looked through the other commands like Depth and Length but I > >don't see anything that does this. > > It seems to me there are two reasonably simple possibilities. You might do > > In[2]:= > {Depth@#-1,Length@#}&/@x > > Out[2]= > {{1, 1}, {1, 2}, {1, 4}} > > which returns a result similar to dimensions, That is the first number specifies the number of rows in the element and the second the number of columns for the element (number of sub-elements). By using Depth you will be notified is one of the elements in x isn't a vector. > > But if you are certain each element of x will be a vector than simply doing > > In[3]:= > Length/@x > > Out[3]= > {1,2,4} > > should suffice > -- > To reply via email subtract one hundred and four