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Post, August 5, 2021 • Modified PGL TauP and SLBM code to utilize identical object definitions. This included: a) modifications to SLBM to wrap all of its objects into the single namespace “SLBM”; b) modifications to PGL/SLBM to wrap all TauP objects into a new namespace “taup”; c) modifications to PGL/SLBM to wrap all utility...

Post, August 5, 2021 • Fixed the constructor in GreatCircle_Xg.cc during the TauPSite initialization to set the TauPSite planet radius before setting the receiver depth.

Post, August 5, 2021 • Changed InterpolatedProfile and all derived classes so that they no longer have to call new to create the data arrays. This involved changing from vector to double[] arrays in many places. Resulted in factor of 3 improvement in execution speed. Fixed bug that prevented SLBM from exiting gracefully when invalid...

Post, August 5, 2021 • Changed the model input file (unified_SLBM.txt) in two ways: (a) the constraint that gradients cannot be negative has been removed from the model input file and is now being imposed in the code. There can now be substantial negative gradients in the input file. (b) There are now 9 layers...

Post, August 5, 2021 • Fixed some bugs having to do with the valid range of the Pn travel time for mantle events. Changed the algorithm for computing Pg/Lg travel times. Code now returns Pg/Lg travel times for events at any depth in the crust, even events below the top of the middle crust. Added...

Post, August 5, 2021 • Modified the method where Pn/Sn travel times are computed for mantle events. Basically made the convergence behavior more robust and imposed a criterion that C * H < 0.2 where C is the Zhao C parameter and H is the depth of the ray turning point below the Moho. Removed...

Post, August 5, 2021 • Fixed a bug in the part of the code that computes Pn/Sn travel times for mantle events. The bug caused the code to hang for events just below the Moho and close to the receiver. The test events seemed to return very similar travel times for very small differences in...

Post, August 5, 2021 • Added new functions to Grid including int getBufferSize() const;void loadVelocityModelBinary(util::DataBuffer& buffer)void saveVelocityModelBinary(util::DataBuffer& buffer) The first function retrieves the approximate size required of a DataBuffer object to store the contents of the Grid object. The next two functions read a Grid object from an input DataBuffer and save the contents of...

Post, August 5, 2021 • Changed the grid from the deformed grid to the global tessellated grid. Added method getVersion() to all the interfaces. Added the following methods to SlbmInterface to support regularization for tomography applications. See html documentation for more information:  void getNodeNeighbors(const int& nid, int neighbors[], int& nNeighbors) void getNodeNeighbors(const int& nid, vector& neighbors) void...

Post, August 5, 2021 • Added several methods to all the SLBM interfaces to facilitate interaction with active nodes. Active nodes are nodes that fall within a user-specified latitude, longitude range. This functionality is really only useful to tomographers.

Post, August 5, 2021 • Converted the model files from ascii to binary format. The binary format is the one specified by AFTAC/QTSI. This change has resulted in a dramatic reduction in the time required to load the velocity models into memory. The ascii format is still supported but support for ascii will be removed...

Post, August 5, 2021 • Modified the way travel time for Pg/Lg phases is calculated. Previously, Pg/Lg travel times were computed with the Headwave method. Starting with this release, Pg/Lg travel times are computed with both the Headwave and TauP methods and the reported travel time is the lesser of the travel times calculated with...

Post, August 5, 2021 • The major change in this release is that the travel time calculations for Pg/Lg phases have been modified to implement the algorithm described by Steve Myers.

Post, August 5, 2021 • This version contains bug fixes for segmentation faults for events in which the source and receiver coincide with each other, and for Pg events where source-receiver distance is greater than ~13 degrees. The SLBMtestc and SLBMtestcc test scripts were enhanced to include a stress test of the Pg calculations. Added...

Post, August 5, 2021 • This version contains bug fix to handle cases when the activenode range spans the dateline correctly. Also, includes changes to the uncertainty units for compatibility w/PGL/UtilLib. Made ch_max (in SLBMInterface) a static variable and renamed it to CH_MAX defaulting to .2. Made the function calls void setCHMax(double chMax)void getCHMax(double& chMax)void...

Post, August 5, 2021 • Added new target (STR) to the makefile to allow rebuilding a 32-bit stand-alone version of the SLBM_Root from a SNL_Tool_Root delivery. Note: SNL_Tool_Root only uses the core SLBM units (not any other language interfaces) and builds only the libSLBM.so library in 64-Bit mode.

Post, August 5, 2021 • Fixed bug that caused SLBM to occasionally segmentation fault for Pg/Lg calculations when using TaupLoc. What was happening was that a velocity stack was defined at the receiver with the bottom at the radius of the Moho at the receiver. The Taup model was constructed with only the velocity stack...

Post, August 5, 2021 • Corrected equation for computing earth radius as a function of latitude. This makes only an insignificantly small difference ( > 0.1 msec).

Post, August 5, 2021 • Added methods to compute derivatives of travel time with respect to source location. New methods are: get_dtt_dlat(double& dtt_dlat)get_dtt_dlon(double& dtt_dlon)get_dtt_ddepth(double& dtt_ddepth)getSlowness(double& slowness)getSlownessUncertainty(double& slownessUncertainty) Renamed method getUncertainty() to getTravelTimeUncertainty(). I also added methods to compute derivatives of slowness with respect to lat, lon and depth: get_dsh_dlat(double& dsh_dlat)get_dsh_dlon(double& dsh_dlon)get_dsh_ddepth(double& dsh_ddepth) but then commented...

Post, August 5, 2021 • Made a change to Zhao equations, replacing 1.58e-4 with 1/r. This dramatically improved the accuracy of the code for mantle events. Also fixed a bug that generated segmentation faults when source depth was exactly equal to Moho depth (to double precision). Added a software disclaimer at the top of every...

Post, August 5, 2021 • Ported all interfaces to Windows and to Linux. Code changes to remove the discontinuitites from the derivatives of tt with respect to source position and spikes from second derivatives of tt with respect to source position. All derivatives are now smooth. Sandia now holds the copyright to the code and...

Post, August 5, 2021 • Added methods to return derivatives of slowness with respect to lat, lon and depth. Modified SlbmInterface methods setGridData() and setActiveNodeData() so that they now include depth as an argument. This means that it is now possible to change the depths of the tops of the interfaces in a model. In...

Post, August 5, 2021 • Fixed a bug in Java interface that caused a very slow memory leak. Only the Java interface is affected.

Post, August 5, 2021 • Changed manner in which derivatives of tt with respect to lat, lon are computed. Removed all derivatives of slowness from all interfaces. Fixed bug related to computing derivative of tt with respect to depth that happened when depth step spanned the Moho. Changed default step size used to compute horizontal...

Post, August 5, 2021 • Fixed some inaccuracies in the documentation. Made minor code changes to address compiler warnings observed when the compiling the Linux version of the code.