simplify, robustness

Author: scivision

.github/workflows/ci.yml

@@ -9,7 +9,7 @@ on:
 jobs:
 
   linux:
-    runs-on: ubuntu-latest
+    runs-on: ubuntu-20.04
     steps:
     - uses: actions/checkout@v2
 

Readme.md

@@ -2,8 +2,10 @@
 
 ![ci](https://github.com/scivision/matlab-hdf5/workflows/ci/badge.svg)
 
-These functions are sorely needed in Matlab itself.
-The NetCDF4 functions also work with GNU Octave when octave-netcdf is installed.
+These HDF5 and NetCDF4 functions should be built into Matlab itself, but since they're not yet, we provide them.
+The NetCDF4 functions also work with GNU Octave when
+[octave-netcdf](https://octave.sourceforge.io/netcdf/index.html)
+is installed.
 
 ## hdf5
 
@@ -59,12 +61,6 @@ The NetCDF4 functions also work with GNU Octave when octave-netcdf is installed.
 
 ## General utilities
 
-* check if a file exists, and is a file (not a folder). Works with very old Matlab and Octave using fallback.
-
-    ```matlab
-    is_file(filename)
-    ```
-
 * Check if running on GNU Octave
 
     ```matlab

expanduser.m

@@ -47,8 +47,13 @@
   end
 
   if isempty(home)
-    % this is 100x slower than getenv() on Matlab R2020a
-    home = char(java.lang.System.getProperty("user.home"));
+    if usejava('jvm')
+      % this is 100x slower than getenv() on Matlab R2020a
+      home = char(java.lang.System.getProperty("user.home"));
+    else
+      % return unmodified
+      return
+    end
   end
 
   expanded = fullfile(home, expanded(2:end));

h5exists.m

@@ -7,15 +7,9 @@
 % exists: boolean
 
 narginchk(2,2)
+validateattributes(filename, {'char'}, {'vector'}, 1)
 validateattributes(varname, {'char'}, {'vector'}, 2)
 
-filename = expanduser(filename);
-
-vars = {};
-if is_file(filename)
-  vars = h5variables(filename);
-end
-
-exists = any(strcmp(vars, varname(2:end)));
+exists = any(strcmp(h5variables(filename), varname(2:end)));
 
 end % function

h5save.m

@@ -21,7 +21,7 @@ function h5save(filename, varname, A, sizeA, dtype)
   sizeA = size(A);
 end
 
-if h5exists(filename, varname)
+if isfile(filename) && h5exists(filename, varname)
   exist_file(filename, varname, A, sizeA)
 else
   new_file(filename, varname, A, sizeA)

h5size.m

@@ -7,6 +7,7 @@
 % fsize: vector of variable size per dimension
 
 narginchk(2,2)
+validateattributes(filename, {'char'}, {'vector'}, 1)
 validateattributes(variable, {'char'}, {'vector'}, 2)
 
 finf = h5info(expanduser(filename), variable);

h5variables.m

@@ -2,11 +2,15 @@
 % get dataset names and groups in an HDF5 file
 narginchk(1,1)
 
-filename = expanduser(filename);
+names = [];
+groups = [];
 
 % use temporary variable to be R2017b OK
-finf = h5info(filename);
+finf = h5info(expanduser(filename));
 ds = finf.Datasets;
+if isempty(ds)
+  return
+end
 
 names = {ds(:).Name};
 

is_file.m

@@ -7,15 +7,9 @@
 % exists: boolean
 
 narginchk(2,2)
+validateattributes(filename, {'char'}, {'vector'}, 1)
 validateattributes(varname, {'char'}, {'vector'}, 2)
 
-filename = expanduser(filename);
-
-vars = {};
-if is_file(filename)
-  vars = ncvariables(filename);
-end
-
-exists = any(strcmp(vars, varname));
+exists = any(strcmp(ncvariables(filename), varname));
 
 end % function

ncexists.m

@@ -32,12 +32,8 @@ function ncsave(filename, varname, A, ncdims, dtype)
   A = coerce_ds(A, dtype);
 end
 
-vars = {};
-if is_file(filename)
-  vars = ncvariables(filename);
-end
 
-if any(strcmp(vars, varname))
+if isfile(filename) && ncexists(filename, varname)
   exist_file(filename, varname, A, sizeA)
 else
   new_file(filename, varname, A, sizeA, ncdims)