Fix for `add_mesh` and Optional Stability Checks

v0.0.63

• Fixed the add_mesh method. It was not working properly after version 0.0.62.
• Made stability checks optional. Stability checks add significant solve time. If you are confident your model is stable, you can skip the stability check by toggling check_stability to False in your call to your analysis command. In the future I may move the stability check out of the analysis commands entirely and make it its own method. The analysis methods are getting complex and this check just adds to that complexity.

Model Stability Checks and Improvements to Meshes

• PyNite now checks for nodal instabilities when analyzing a model. If nodal instabilities are found, PyNite will output the unstable nodes and directions to the console, and will throw an exception.
• Added a method called rename to the FEModel3D class for quickly renaming all the nodes and elements in the model in sequential order.
• Added a last_node and last_element attribute to the mesh class. These methods can be used to get the name of the last node or element in a mesh.
• Improved the reliability of the add_mesh method. It now can handle adding meshes containing node and element names already defined in the model. It automatically resolves the duplicate names.

Bug Fix for Openings in Meshes

• Fixed a bug that caused some mesh openings to crash models.

Bug Fix for Small Openings in Meshes

• Fixed a stubborn bug that wouldn't create openings if they didn't have a node inside them. This prevented openings from showing up in small meshes.
• Added unit testing to help identify similar problems with mesh openings in the future.

Bug Fix for Small Openings in Meshes

v0.0.59

Update for v.0.0.59

Bug fix for bug fix

Fixing a stubborn bug (I think) that should've been fixed on v0.0.57.

Bug Fix for Small Openings in Meshes

Bug fix for small openings that weren't being added to meshes.

Bug Fix for Orthotropic Rectangular Plates

• Bug fix for orthotropic rectangular plates. The stiffness was slightly off on rectangular plates in version 0.0.55. Prior versions were not affected. Version 0.0.55 was the latest version for less than 24 hours, so this bug shouldn't have affected most models users have built.
• Added unit testing for in-plane (membrane) behavior, and stiffness modification factors to identify issues faster in the future. PyNite solutions matched theoretical solutions within 0.1% for uncracked sections, and within 2% for cracked sections. Very good performance for in-plane behavior.

Orthotropic Plates & Quads

• Added stiffness modification factors for rectangular plate and quarilateral elements. Orthotropic in-plane behavior can now be modeled. This can be used to model the cracked stiffness of concrete and masonry for in-plane loads. Exercise caution when using this feature. These factors only apply to in-plane stiffnesses in the element's local x and y directions. Out-of-plane stiffnesses are not modified. Ensure element local axes are aligned to the directions you want to apply the stiffness modifications to.
• The arguments for many methods relating to rect plates and quads have been reorganized with the addition of the stiffness modification factors. With this update any plate/quad models you have will likely need to be updated.
• Reformulated rectangular plate element in-plane (membrane) forces. These elements are now isoparametric just like the quad elements. This was done to make them orthotropic.
• Improved docstrings for plates and quads.

Bug Fixes for Member Global Point Loads and Rendering

• Bug fix for member point loads applied in a global direction. They were overriding the member end forces due to an ambiguous variable name.
• Bug fix for rendering. Several variable names had underscores that didn't belong there. It was causing rendering errors. See version 0.0.53 notes for a full list of what's been changing with regard to rendering.