ncsave: require dimensions for non-scalar

Author: scivision

+stdlib/+hdf5nc/ncsave.m

@@ -4,7 +4,7 @@ function ncsave(filename, varname, A, opts)
   filename (1,1) string {mustBeNonzeroLengthText}
   varname (1,1) string {mustBeNonzeroLengthText}
   A {mustBeNonempty}
-  opts.dims cell = {}
+  opts.dims cell
   opts.type string {mustBeScalarOrEmpty} = string.empty
 end
 
@@ -15,42 +15,28 @@ function ncsave(filename, varname, A, opts)
 % avoid creating confusing file ./~/foo.nc
 filename = stdlib.fileio.expanduser(filename);
 
-if isempty(opts.dims)
-  if isscalar(A)
-    sizeA = 1;
-    ncdims = [];
-  elseif isvector(A)
-    sizeA = length(A);
-    ncdims = {'x', sizeA};
-  elseif ismatrix(A)
-    sizeA = size(A);
-    ncdims = {'x', sizeA(1), 'y', sizeA(2)};
-  else
-    sizeA = size(A);
-    switch length(sizeA)
-      case 3, ncdims = {'x', sizeA(1), 'y', sizeA(2), 'z', sizeA(3)};
-      case 4, ncdims = {'x', sizeA(1), 'y', sizeA(2), 'z', sizeA(3), 'w', sizeA(4)};
-      otherwise, error('ncsave currently does scalar through 4D')
-    end
-  end % if
-else
-  ncdims = opts.dims;
+% coerce if needed
+A = coerce_ds(A, opts.type);
 
+if isscalar(A)
+  sizeA = 1;
+else
+  if isempty(opts.dims)
+    error("For non-scalar NetCDF variables, the dimenions must be defined as a cell array")
+  end
   for i = 2:2:length(opts.dims)
     sizeA(i/2) = opts.dims{i}; %#ok<AGROW>
   end
 end
-% coerce if needed
-A = coerce_ds(A, opts.type);
 
 if isfile(filename)
   if stdlib.hdf5nc.ncexists(filename, varname)
     nc_exist_file(filename, varname, A, sizeA)
   else
-    nc_new_file(filename, varname, A, sizeA, ncdims)
+    nc_new_file(filename, varname, A, sizeA, opts.dims)
   end
 else
-  nc_new_file(filename, varname, A, sizeA, ncdims)
+  nc_new_file(filename, varname, A, sizeA, opts.dims)
 end
 
 end

+stdlib/+hdf5nc/private/nc_new_file.m

@@ -2,22 +2,22 @@ function nc_new_file(filename, varname, A, sizeA, ncdims)
 
 if isscalar(A)
   nccreate(filename, varname, ...
-      "Datatype", class(A), ...
-      "Format", 'netcdf4')
+      Datatype=class(A), ...
+      Format='netcdf4')
 elseif isvector(A) || ischar(A) || isstring(A)
   nccreate(filename, varname, ...
-      "Dimensions", ncdims, ...
-      "Datatype", class(A), ...
-      "Format", 'netcdf4')
+      Dimensions=ncdims, ...
+      Datatype=class(A), ...
+      Format='netcdf4')
 else
   % enable Gzip compression--remember Matlab's dim order is flipped from
   % C / Python
   nccreate(filename, varname, ...
-    "Dimensions", ncdims, ...
-    "Datatype", class(A), ...
-    "DeflateLevel", 1, "Shuffle", true, ...
-    "ChunkSize", stdlib.hdf5nc.auto_chunk_size(sizeA), ...
-    "Format", 'netcdf4')
+    Dimensions=ncdims, ...
+    Datatype=class(A), ...
+    DeflateLevel=1, Shuffle=true, ...
+    ChunkSize=stdlib.hdf5nc.auto_chunk_size(sizeA), ...
+    Format='netcdf4')
 end
 
 ncwrite(filename, varname, A)

+stdlib/ncsave.m

@@ -8,6 +8,5 @@ function ncsave(filename, varname, A, opts)
   opts.type string {mustBeScalarOrEmpty} = string.empty
 end
 
-stdlib.hdf5nc.ncsave(filename, varname, A, ...
-'dims', opts.dims, 'type', opts.type)
+stdlib.hdf5nc.ncsave(filename, varname, A, dims=opts.dims, type=opts.type)
 end

test/TestNetCDF.m

@@ -15,6 +15,9 @@ function setup_path(tc)
 function setup_file(tc)
 import matlab.unittest.constraints.IsFile
 import matlab.unittest.fixtures.TemporaryFolderFixture
+
+tc.assumeFalse(isMATLABReleaseOlderThan('R2021a'), "NetCDF requires Matlab >= R2021a")
+
 fixture = tc.applyFixture(TemporaryFolderFixture);
 
 A0 = 42.;
@@ -41,15 +44,15 @@ function setup_file(tc)
 
 % create test data first, so that parallel tests works
 stdlib.ncsave(basic, 'A0', A0)
-stdlib.ncsave(basic, 'A1', A1)
+stdlib.ncsave(basic, 'A1', A1, "dims", {'x1', size(A1,1)})
 stdlib.ncsave(basic, 'A2', A2, "dims", {'x2', size(A2,1), 'y2', size(A2,2)})
 stdlib.ncsave(basic, 'A3', A3, "dims", {'x3', size(A3,1), 'y3', size(A3,2), 'z3', size(A3,3)})
 stdlib.ncsave(basic, 'A4', A4, "dims", {'x4', size(A4,1), 'y4', size(A4,2), 'z4', size(A4,3), 'w4', size(A4,4)})
 
 if ~isMATLABReleaseOlderThan('R2021b')
   stdlib.ncsave(basic, "utf0", utf0)
-  stdlib.ncsave(basic, "utf1", utf1)
-  stdlib.ncsave(basic, "utf2", utf2)
+  stdlib.ncsave(basic, "utf1", utf1, "dims", {'s1', size(utf1, 1)})
+  stdlib.ncsave(basic, "utf2", utf2, "dims", {'s1', size(utf2, 1), 't1', size(utf2, 2)})
 end
 
 stdlib.ncsave(basic, '/t/x', 12)
@@ -226,7 +229,8 @@ function test_rewrite(tc)
 import matlab.unittest.constraints.IsFile
 basic = tc.TestData.basic;
 
-stdlib.ncsave(basic, "A2", 3*magic(4))
+A2 = 3*magic(4);
+stdlib.ncsave(basic, "A2", A2, "dims", {'x2', size(A2,1), 'y2', size(A2,2)})
 
 tc.assumeThat(basic, IsFile)
 tc.verifyEqual(ncread(basic, 'A2'), 3*magic(4))