h5save/ncsave: check destination folder exists to avoid confusing error

Author: scivision

h5save.m

@@ -1,4 +1,7 @@
 function h5save(filename, varname, A, sizeA, dtype)
+% H5SAVE
+% create or append to HDF5 file
+% parent folder (file directory) must already exist
 
 narginchk(3, 5)
 
@@ -31,6 +34,7 @@ function h5save(filename, varname, A, sizeA, dtype)
 
 
 function exist_file(filename, varname, A, sizeA)
+narginchk(4,4)
 
 diskshape = h5size(filename, varname);
 if length(diskshape) >= 2
@@ -54,6 +58,10 @@ function exist_file(filename, varname, A, sizeA)
 
 
 function new_file(filename, varname, A, sizeA)
+narginchk(4,4)
+
+folder = fileparts(filename);
+assert(isfolder(folder), '%s is not a folder, cannot create %s', folder, filename)
 
 if isvector(A)
   h5create(filename, varname, sizeA, 'DataType', class(A))

h5variables.m

@@ -1,6 +1,6 @@
-function [names, groups] = h5variables(filename)
+function [names, groups] = h5variables(filename, group)
 % get dataset names and groups in an HDF5 file
-narginchk(1,1)
+narginchk(1,2)
 
 names = [];
 groups = [];
@@ -11,11 +11,20 @@
 if isempty(ds)
   return
 end
+if nargin > 1
+  gs = finf.Groups;
+  i = contains({gs(:).Name}, group);
+  if ~any(i)
+    return
+  end
+  ds = gs(i).Datasets;
+end
 
 names = {ds(:).Name};
 
 if nargout > 1
-  groups = {finf.Groups};
+  gs = finf.Groups;
+  groups = {gs.Name};
 end
 
 end % function

ncsave.m

@@ -61,6 +61,10 @@ function exist_file(filename, varname, A, sizeA)
 function new_file(filename, varname, A, sizeA, ncdims)
 narginchk(5,5)
 
+folder = fileparts(filename);
+assert(isfolder(folder), '%s is not a folder, cannot create %s', folder, filename)
+
+
 if isscalar(A)
   nccreate(filename, varname, 'Datatype', class(A), 'Format', 'netcdf4')
 elseif isvector(A)