Gmsh python code#
Gmsh python series#

In this way, you can prune the search space if such a character were to appear in the query, and you can test for this in constant time. You can count all character frequencies in both strings with a histogram which can be done in O(N) time. The next potential speedup is to recognize that any character which does not appear exactly the same number of times in both strings will instantly be a failed match. The test for membership is then basically the cost of an array lookup (and you can save operations by not doing the subtraction - instead just make the array larger and index directly by character. Alternatively, you can have an 18-value array and index it by character ( c - 'a' would give a value between 0 and 17).The set of allowed characters is now a mask with these bits ORed together and you can test membership of a character with a bitwise-AND Represent every letter as a single bit - now every character is an 18-bit value with only one bit set.The first obvious speedup is to ensure your set membership test is O(1). However, I was told that there was a way to solve this faster in O(N). Each query takes O(N) time to process, and there are N queries, for a total of O(N^2) time. Otherwise, the s1 and s2 are equal when restricted only to letters in the query. If at some point, the characters don't match, then the strings are not equal. I was able to solve this in O(N^2) time by doing the following: For each query, I checked if s1 and s2 would be equal by iterating through both strings, one character at a time, skipping the characters that do not lie within the subset of allowed characters, and checking to see if the 'allowed' characters from both s1 and s2 match. These don't match, so the query would return false. S1 and s2 can contain up to 10^5 characters, and there are up to 10^5 queries.įor instance, if s1 is 'aabcd' and s2 is 'caabd', and you are asked to process a query with the subset 'ac', then s1 becomes 'aac' while s2 becomes 'caa'. For each query, determine whether s1 and s2, when restricted only to the letters in the query, are equal. Each query provides a subset of lowercase English letters from 'a' through 'r'.

Gmsh python series#

('Mesh.CharacteristicLengthMax', 0.4) įactory.addCylinder(-2*R,0,0, 4*R,0,0, Rs, 4)įactory.addCylinder(0,-2*R,0, 0,4*R,0, Rs, 5)įactory.addCylinder(0,0,-2*R, 0,0,4*R, Rs, 6)įactory.You are given two strings, s1 and s2, comprised entirely of lowercase letters 'a' through 'r', and need to process a series of queries.

Gmsh python code#

This example can also be downloaded from the source code of GMSH: # This reimplements gmsh/demos/boolean/boolean.geo in Python. Let us redo the CAD example using the Python API. Using Python API, rebuild the “L-shape” geometry. Should open a GMSH window with a meshed disk Launching it via the following command python mycircle.py The less you launch it, the better it is for performance purpose

# This command is mandatory and synchronize CAD with GMSH Model. Lines.append((points,center,points))Ĭurveloop = ()ĭisk = () # Create Point for the center of the circleĬenter = (0,0,0, h, 10) # Ask GMSH to display information in the terminal The code can be the following: import gmsh Let start with a circle centered on (0,0) of radius R=1. For example, adding a point ( Point(i)=) becomes (x,y,z,h,i).

Everything you learn prior to this part is still valid (and will actually help you), only the syntax changes (good news!).

This tutorial only uses Python but both C++ and Julia work with the SDK!.

In particular, you should definitely have a look at t1.py, t2.py, t3.py, … where the commands are very well detailed and explained. Numerous detailed examples are given in the source code of GMSH.This section assumes that you are familiar with GMSH inner languages and Python.