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Glenn, Though we've already discussed this, I'm sending this anyway to get it into the archives, so I can just look it up when the question comes up again. > I was digging through some netcdf archives, and > discovered reference to "netcdf v3.0" in correspondence > I had with Mark Rivers in October 1992! > > Was this just my mistake at the time, or was the a version > discontinuty at some point? Here's the chronology, as best I can reconstruct: Version Date of announcement 1.05 1990-01 1.06 1990-07 1.07 1990-07 1.08 1990-08 1.09 1990-10 1.10 1990-10 1.11 1991-03 2.0 beta 1991-10 2.0 1991-11 2.01 1991-11 2.02 1991-12 2.3 beta 1993-03 2.3 1993-04 2.3.1 1993-05 2.3.2 1993-06 2.3.2pl1 1993-06 2.3.2pl2 1993-06 2.3.2pl3 1994-07 2.3.2pl4 1995-01-31 2.4 beta1 1995-10-11 2.4 beta2 1995-10-13 2.4 beta3 1995-11-13 2.4 beta5 1995-12-06 2.4 beta6 1996-01-08 2.4 1996-02-28 2.4.1 1996-03-19 2.4.2 1996-05-02 2.4.3 1996-08-12 3.1a 1996-08-30 In February 1993, we were discussing whether to call the next version 2.3 or 3.0 (I believe you favored 3.0), but we ultimately decided on 2.3. I've appended a note sent to the netcdfgroup mailing list about this time that confirms this. There was never a version 3.0 announced or released, as far as I can determine. --Russ From address@hidden Mon Feb 1 07:10:27 1993 Received: by unidata.ucar.edu id AA28658 (5.65c/IDA-1.4.4 for netcdfgroup-send); Mon, 1 Feb 1993 14:10:30 -0700 Received: from buddy.unidata.ucar.edu by unidata.ucar.edu with SMTP id AA28654 (5.65c/IDA-1.4.4 for <address@hidden>); Mon, 1 Feb 1993 14:10:28 -0700 Organization: . Keywords: 199302012110.AA28654 Received: by buddy.unidata.ucar.edu id AA21638 (5.65c/IDA-1.4.3 for address@hidden); Mon, 1 Feb 1993 14:10:27 -0700 Date: Mon, 1 Feb 1993 14:10:27 -0700 From: Russ Rew <address@hidden> Message-Id: <address@hidden> To: address@hidden Subject: new release delayed a bit Hi, First a reminder: administrative requests to be added to or deleted from this mailing list should be sent to address@hidden, *not* address@hidden. Question 4 in the NetCDF Frequently Asked Questions list is: 4: When will the next version be available? What changes are included? The previous answer was that we would have the next version available in January 1993, but January is over and the new version is not quite ready yet. We hope to have a beta release available in another week or two. I'm just calling it "the new version" because we're still discussing whether to call it netCDF 2.3 or netCDF 3.0. We are making no incompatible changes in the interface, but the additions of some new functions may justify a new release number. Here's the updated answer to Question 4 in the FAQ list (pub/netcdf/FAQ on unidata.ucar.edu): A: We hope to make the next version available in February 1993. It contains bug fixes, portability enhancements, performance enhancements, and new capabilities. We implemented some new optimizations for the library that result in significant speedups for accessing cross-sections involving non-contiguous data. New capabilities include some additional interfaces that provide a more general form of hyperslab access. This supports sub-sampling along specified dimensions and a mapping between the points of the hyperslab and the memory locations of the corresponding values. In a generalized hyperslab, an index mapping vector is used to define the mapping between points in the generalized hyperslab and the memory locations of the corresponding values, so data values that are written or read need no longer be contiguous in memory. There are also some new interfaces that can be used to write, read, and inquire about records, where a record may contain multiple variables of different types and shapes. Where before you had to access a record's worth of data using multiple calls, now you will be able to use a single call. The ncdump utility supports several new command-line options including the ability to specify for which variables data values will be output, to provide brief annotations in the form of CDL comments to identify data values for large multidimensional variables, or to provide full annotations in the form of trailing CDL comments for every data value. The new release also includes a prototype implementation of a C++ interface for the netCDF data access library. It provides all the functionality of the C interface, improves type safety by eliminating all use of void* pointers, and is somewhat simpler to use than the C interface. With the C++ interface no IDs are needed for netCDF components, there is no need to specify types when creating attributes, and less indirection is required for dealing with dimensions. However, since this is a prototype interface and implementation, it may be changed before a supported version is released. ________________________________________________________________________ Russ Rew Unidata Program Center address@hidden UCAR, PO Box 3000 Boulder, CO 80307-3000