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- {"config":{"lang":["en"],"min_search_length":3,"prebuild_index":false,"separator":"[\\s\\-]+"},"docs":[{"location":"","text":"Welcome to Jupyter Sketcher Documentation Problem solved When you need to solve a mechanical problem, sooner or later you are going to sketch a figure to capture problem's parameters and variables. The better documented, the easier the problem is to resolve for the designer, and the easier it is for others to understand how it is actually solved. What if you could capture this in the program solving the problem and use it as a repository for all definitions and physical variables? This is what jupytersketcher (name of pysketcher module) is proposing to solve. Of course, this makes even more sense when using Jupyter notebooks, because as a sketch not only the image of the solved problem can be displayed, but the dictionary of all variables processed in the notebook for solving physics is used to draw the image and at the same time to solve the equations of motion. jupytersketcher is another small step to help building reusable science. Getting Started You can use the binder link in jupytersketcher Github to see some experiments with pysketcher. pysketcher features Drawing sketches on a matplotlib widget for Jupyter Notebook server or Lab Defining a yaml based \"grammar\" to define sketches Animating sketches within the notebook Main benefit With Pysketcher for Jupyter mechanical notebooks, you get a single copy of the description of the problem and a space to simulate and show the user how the system behaves","title":"Home"},{"location":"#welcome-to-jupyter-sketcher-documentation","text":"","title":"Welcome to Jupyter Sketcher Documentation"},{"location":"#problem-solved","text":"When you need to solve a mechanical problem, sooner or later you are going to sketch a figure to capture problem's parameters and variables. The better documented, the easier the problem is to resolve for the designer, and the easier it is for others to understand how it is actually solved. What if you could capture this in the program solving the problem and use it as a repository for all definitions and physical variables? This is what jupytersketcher (name of pysketcher module) is proposing to solve. Of course, this makes even more sense when using Jupyter notebooks, because as a sketch not only the image of the solved problem can be displayed, but the dictionary of all variables processed in the notebook for solving physics is used to draw the image and at the same time to solve the equations of motion. jupytersketcher is another small step to help building reusable science.","title":"Problem solved"},{"location":"#getting-started","text":"You can use the binder link in jupytersketcher Github to see some experiments with pysketcher.","title":"Getting Started"},{"location":"#pysketcher-features","text":"Drawing sketches on a matplotlib widget for Jupyter Notebook server or Lab Defining a yaml based \"grammar\" to define sketches Animating sketches within the notebook","title":"pysketcher features"},{"location":"#main-benefit","text":"With Pysketcher for Jupyter mechanical notebooks, you get a single copy of the description of the problem and a space to simulate and show the user how the system behaves","title":"Main benefit"},{"location":"about/","text":"In summer 2020 I discovered Pysketcher as I was looking for a way to create Physics sketches for both design and simulation. My second requirement is to have sketches available in Jupyter notebooks (Lab or notebook server) Pysketch was developped in 2012 by Hans Petter Langtangen , see it in GitHub . At that time, Jupyter was emerging and Pysketch was developped as a standalone application. I just need to upgrade it to make it compatible with Jupyter: This is the inception of Jupyter Sketch project! A sketch capturing the dry friction case How it is structured: the composition hierarchy","title":"About"},{"location":"sketcher/","text":"A language to describe a sketch Pysketcher initial version HPL Pysketcher enable sketch definition in python. HPL is showing the hierachical nature of sketches. This is implemented via the Composition function. One can further grasp this using the graphviz_dot function applied to discover the composition herarchy implemented as a graphviz image see The hierarchy of the \"friction\" main object at the end of this page. Due to the hierarchical nature of sketches, it is quite straightforward to think about using yaml as the syntax for defining a sketch. The benefits are as follow: A leaner presentation of the sketch as only the data making sense is going to be used A more straightforward reading of the composition hierachy A more robust sketch definition as only a set of rules will be applied to define a sketch and no further python idiom will be intermingled Example This example provides the yaml content to define the Dry Friction case The final sketch An inclined plan (the A-B edge) supports a blue rectangle which is pulled donward by the gravity. The plan makes an angle \\theta \\theta . The sketch design enable the \\theta \\theta angle to change. The whole plan including the body can rotate arround the point B. The yaml definition Sketcher language is defined as a yaml compliant file or string. The yaml file is a dictionnary of functionnal objects (leaf objects, like Rectangle, Circle, Line etc or composition) extended with object style (line or fill colors, line stroke...) to which transformation are applied (translation, rotation...) As a general rule, a new object suppose all parameters to be defined before they are used to construct it. For example, you can create a circle if the center and the radius have been defined earlier in the file. The general layout of a sketcher file is as follow: Libraries, Construction Variables, Frame declaration of the libraries used by the objects further declared: at least pysketcher is mandatory various global variable which encompass the \"Construction\" variables which define the object main physical dimensions, positions... some \"actions\" corresponding to executable python sentences One mandatory action is the setting of the drawing frame (drawing_tool.set_coordinate_system): it must be declared before any other pysketcher object is used. Other use case of action is the setting of global parameters like default line color: (drawing_tool.set_linecolor('black')) for example Objects Usually starting with the declaration of leaf simple objects then aggregated using the composition object Composition can be made of composition object grouping leafs and composition will be further used to apply transformation latter on (based on the \"physics\") The example presents three group of objects The body object The plan object The friction main object The plan includes the body The friction includes the plan (that will be able to rotate as a group) and the ground (will stay fixed) Libraries, Construction Variables, Frame libraries: [\"from math import tan, radians, sin, cos\", \"from pysketcher import *\"] fontsize: 18 g: 9.81 # constant gravity theta: 30.0 # inclined plane angle L: 10.0 # sketch sizing parameter a: 1.0 # xmin: 0.0 # sketech min Abscissa ymin: -3.0 # sketech min Ordinate rl: 2.0 # rectangle width rL: 1.0 # rectangle length setframe: # sketch setup action: \"drawing_tool.set_coordinate_system(xmin=xmin-L/5, xmax=xmin+1.5*L,ymin=ymin, ymax=ymin+1.5*L,instruction_file='tmp_mpl_friction.py')\" setblackline: # default frame values and actions action: \"drawing_tool.set_linecolor('black')\" B: point(a+L,0) # wall right end A: point(a,tan(radians(theta))*L) # wall left end normal_vec: point(sin(radians(theta)),cos(radians(theta))) # Vector normal to wall tangent_vec: point(cos(radians(theta)),-sin(radians(theta))) # Vector tangent to wall help_line: Line(A,B) # wall line x: a + 3*L/10. y: help_line(x=x) contact: point(x, y) c: contact + rL/2*normal_vec The body object rectangle: formula: Rectangle(contact, rl, rL) style: linecolor: blue filled_curves: blue transform: [\"rotate(-theta, contact)\", \"translate(-rl/2*tangent_vec)\"] N: formula: Force(contact - rl*normal_vec, contact, r'$N$', text_pos='start') style: linecolor: black mg: formula: Gravity(c, rl, text='$Mg$') style: linecolor: black wheel: formula: \"Composition({'outer': rectangle})\" style: shadow: 1 body: formula: \"Composition({'wheel': wheel, 'N': N, 'mg': mg})\" style: linecolor: black The plan object mB: formula: Text(r'$B$',B) mA: formula: Text(r'$A$', A) wall: formula: Wall(x=[A[0], B[0]], y=[A[1], B[1]], thickness=-0.25,transparent=False) style: linecolor: black angle: formula: \"Arc_wText(r'$<bslash>theta$', center=B, radius=3, start_angle=180-theta, arc_angle=theta, fontsize=fontsize)\" style: linecolor: black linewidth: 1 ground: formula: Line((B[0]-L/10., 0), (B[0]-L/2.,0)) stlye: linecolor: black linestyle: dashed linewidth: 1 x_const: formula: Line(contact, contact + point(0,4)) style: linestyle: dotted transform: rotate(-theta, contact) x_axis: formula: \"Axis(start=contact+ 2*rl*normal_vec, length=2*rl,label='$x$', rotation_angle=-theta)\" plan: formula: \"Composition({'body': body, 'angle': angle, 'inclined wall': wall, 'x start': x_const, 'x axis': x_axis, 'mA': mA, 'mB': mB})\" The friction main object friction: formula: \"Composition({'plan': plan, 'ground': ground})\" The hierarchy of the \"friction\" main object","title":"Sketcher definition"},{"location":"sketcher/#a-language-to-describe-a-sketch","text":"Pysketcher initial version HPL Pysketcher enable sketch definition in python. HPL is showing the hierachical nature of sketches. This is implemented via the Composition function. One can further grasp this using the graphviz_dot function applied to discover the composition herarchy implemented as a graphviz image see The hierarchy of the \"friction\" main object at the end of this page. Due to the hierarchical nature of sketches, it is quite straightforward to think about using yaml as the syntax for defining a sketch. The benefits are as follow: A leaner presentation of the sketch as only the data making sense is going to be used A more straightforward reading of the composition hierachy A more robust sketch definition as only a set of rules will be applied to define a sketch and no further python idiom will be intermingled","title":"A language to describe a sketch"},{"location":"sketcher/#example","text":"This example provides the yaml content to define the Dry Friction case","title":"Example"},{"location":"sketcher/#the-final-sketch","text":"An inclined plan (the A-B edge) supports a blue rectangle which is pulled donward by the gravity. The plan makes an angle \\theta \\theta . The sketch design enable the \\theta \\theta angle to change. The whole plan including the body can rotate arround the point B.","title":"The final sketch"},{"location":"sketcher/#the-yaml-definition","text":"Sketcher language is defined as a yaml compliant file or string. The yaml file is a dictionnary of functionnal objects (leaf objects, like Rectangle, Circle, Line etc or composition) extended with object style (line or fill colors, line stroke...) to which transformation are applied (translation, rotation...) As a general rule, a new object suppose all parameters to be defined before they are used to construct it. For example, you can create a circle if the center and the radius have been defined earlier in the file. The general layout of a sketcher file is as follow: Libraries, Construction Variables, Frame declaration of the libraries used by the objects further declared: at least pysketcher is mandatory various global variable which encompass the \"Construction\" variables which define the object main physical dimensions, positions... some \"actions\" corresponding to executable python sentences One mandatory action is the setting of the drawing frame (drawing_tool.set_coordinate_system): it must be declared before any other pysketcher object is used. Other use case of action is the setting of global parameters like default line color: (drawing_tool.set_linecolor('black')) for example Objects Usually starting with the declaration of leaf simple objects then aggregated using the composition object Composition can be made of composition object grouping leafs and composition will be further used to apply transformation latter on (based on the \"physics\") The example presents three group of objects The body object The plan object The friction main object The plan includes the body The friction includes the plan (that will be able to rotate as a group) and the ground (will stay fixed)","title":"The yaml definition"},{"location":"sketcher/#libraries-construction-variables-frame","text":"libraries: [\"from math import tan, radians, sin, cos\", \"from pysketcher import *\"] fontsize: 18 g: 9.81 # constant gravity theta: 30.0 # inclined plane angle L: 10.0 # sketch sizing parameter a: 1.0 # xmin: 0.0 # sketech min Abscissa ymin: -3.0 # sketech min Ordinate rl: 2.0 # rectangle width rL: 1.0 # rectangle length setframe: # sketch setup action: \"drawing_tool.set_coordinate_system(xmin=xmin-L/5, xmax=xmin+1.5*L,ymin=ymin, ymax=ymin+1.5*L,instruction_file='tmp_mpl_friction.py')\" setblackline: # default frame values and actions action: \"drawing_tool.set_linecolor('black')\" B: point(a+L,0) # wall right end A: point(a,tan(radians(theta))*L) # wall left end normal_vec: point(sin(radians(theta)),cos(radians(theta))) # Vector normal to wall tangent_vec: point(cos(radians(theta)),-sin(radians(theta))) # Vector tangent to wall help_line: Line(A,B) # wall line x: a + 3*L/10. y: help_line(x=x) contact: point(x, y) c: contact + rL/2*normal_vec","title":"Libraries, Construction Variables, Frame"},{"location":"sketcher/#the-body-object","text":"rectangle: formula: Rectangle(contact, rl, rL) style: linecolor: blue filled_curves: blue transform: [\"rotate(-theta, contact)\", \"translate(-rl/2*tangent_vec)\"] N: formula: Force(contact - rl*normal_vec, contact, r'$N$', text_pos='start') style: linecolor: black mg: formula: Gravity(c, rl, text='$Mg$') style: linecolor: black wheel: formula: \"Composition({'outer': rectangle})\" style: shadow: 1 body: formula: \"Composition({'wheel': wheel, 'N': N, 'mg': mg})\" style: linecolor: black","title":"The body object"},{"location":"sketcher/#the-plan-object","text":"mB: formula: Text(r'$B$',B) mA: formula: Text(r'$A$', A) wall: formula: Wall(x=[A[0], B[0]], y=[A[1], B[1]], thickness=-0.25,transparent=False) style: linecolor: black angle: formula: \"Arc_wText(r'$<bslash>theta$', center=B, radius=3, start_angle=180-theta, arc_angle=theta, fontsize=fontsize)\" style: linecolor: black linewidth: 1 ground: formula: Line((B[0]-L/10., 0), (B[0]-L/2.,0)) stlye: linecolor: black linestyle: dashed linewidth: 1 x_const: formula: Line(contact, contact + point(0,4)) style: linestyle: dotted transform: rotate(-theta, contact) x_axis: formula: \"Axis(start=contact+ 2*rl*normal_vec, length=2*rl,label='$x$', rotation_angle=-theta)\" plan: formula: \"Composition({'body': body, 'angle': angle, 'inclined wall': wall, 'x start': x_const, 'x axis': x_axis, 'mA': mA, 'mB': mB})\"","title":"The plan object"},{"location":"sketcher/#the-friction-main-object","text":"friction: formula: \"Composition({'plan': plan, 'ground': ground})\"","title":"The friction main object"},{"location":"sketcher/#the-hierarchy-of-the-friction-main-object","text":"","title":"The hierarchy of the \"friction\" main object"}]}
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